FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 FASTLEARN EXAMINER 8–9 TOPICAL REVISION MATHEMATICS NEW SYLLABUS PAST EXAM QUESTIONS 2011 – 2017 Mwiya Namakando Construction diagrams by Rabson K. Banda Cover design by Nelson Nkhoma ©2017 FASTLEARN PUBLISHERS 1 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM TABLE OF CONTENTS – TOPICS Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 2011 – 2017 Topical Revision Guide Questions Answers 1 SETS …………………………………………………………………......................... 4 43 2 EVALUATION (INTERGERS, INDICES, REAL NUMBERS) ……………… 7 46 3 APPROXIMATION & ESTIMATION ................................................ 9 51 4 SIMPLIFICATION ……………………………………………………………………… 10 56 5 FRACTIONS, DECIMALS & PERCENTAGES 11 58 6 FACTORISATION ……………………………………………………………………….. 11 59 7 RATIO & PROPORTION ……………………………………………………………… 12 60 8 CHANGE THE SUBJECT OF THE FORMULA ………………………………… 13 62 9 SOCIAL & COMMERCIAL ARITHMETIC ………………………………………. 13 63 10 CARTESIAN PLANE …………………………………………………………………….. 16 69 11 FUNCTIONS ……………………………………………………………………………….. 18 72 12 SHAPES AND SYMMETRY ………………………………………………….. …….. 19 73 13 POLYGONS ………………………………………………………………………………... 20 75 14 MENSURATION ………………………………………………………………….……… 21 77 15 ANGLES 82 16 GEOMETRICAL CONSTRUCTION ………………………………………….. 27 84 17 STATISTICS ………………………………………………………………………………….. 28 90 18 NUMBER BASES 96 19 SEQUENCES ……………………………………………………………………………….. 33 108 20 PYTHAGORAS’ THEOREM …………………………………………………………… 33 109 21 BEARINGS ………………………………………………………………………………….. 35 110 22 EQUATIONS ……………………………………………………………………............ 35 111 23 INEQUATIONS …………………………………………………………………… ………. 36 113 24 SIMULTENEOUS EQUATIONS ……………………………………………………… 38 116 …………………………… …………………………………………………………………………….. 24 ……………………………………………………………….. 32 2 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, TOPIC Mathematics 8 - 9 0968-747007, 0955-747000 Questions Answers 25 SIMILARITY & CONGRUENCY ……………………………………………………… 38 122 27 MATRICES …………………………………………………………………………………. 41 125 28 COMPUTER STUDIES ……………………………………………………………….. 42 127 29 PROBABILITY …………………………………………………………………………… 128 3 43 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 1 SETS 1 The diagram below shows sets A and B. Call 0977-747000, List the elements of π′ ∩ π. {π, π, π} π΄ {π, π, π, β} π΅ {π, π, π} πΆ π· {π, π, π} 4 List the sets: (a) A ∪ B (b) A’ ∩ B’ Use set notation to describe the shaded region. [2016.P2.Q2(a)] Given that E = {1, 2, 3, 4, 5, 6, 7, 8, 9}, A = (1, 2, 4,5}, B = (2, 4, 6, 7} and C = (2, 3, 5, 7, 8}. (i) illustrate this information in the Venn diagram below. 3 [2015.P1.Q18] The Venn diagram below illustrates sets A and B. [2016.P1.Q20(a)] [2016.P1.Q20(b)] 2 (ii) Mathematics 8 - 9 0968-747007, 0955-747000 5 [2015.P2.Q4a] πΊππ£ππ π‘βππ‘ πΈ = {π₯: π₯ < 10, π₯ ∈ π}, π = {πππππ ππ’πππππ ππ πΈ}, π = {ππ£ππ ππ’πππππ ππ πΈ} πππ π = {ππππ‘πππ ππ 6}. (i) Illustrate this information in the Venn diagram below. πΏππ π‘ π‘βπ πππππππ‘π ππ π‘βπ π ππ‘ (π΄ ∪ π΅)′ ∩ πΆ. [2015.P1.Q4] The Venn diagram below shows sets P and Q. (ii) List the elements of (P ∪ R)’ ∩ Q. 6 . ECZ-2013-P2-Q8(b) In the diagram below, shade the region (PUG)'. [1] 4 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 List the set M’. 9 ECZ-2012-P2-Q5(c) In a group of 24 people, 12 had umbrellas, 10 had raincoats, 7 had both and the rest had neither. Illustrate this information on the Venn diagram below. [3] 7(i) ECZ-2013-P2-Q1(d)(i) In a group of 30 pupils, all play either Netball or Volleyball. 23 pupils play Netball and 19 play Volleyball. Complete the Venn diagram below to illustrate this information. [2] 10(i) ECZ-2012-P2-Q2(c)(i) The Venn diagram below shows set A and B. (ii) ECZ-2013-P2-Q1(d)(ii) How many pupils play one game only? [1] πΉπππ π(π΄ ∪ π΅)′ . 8 ECZ-2013-P1-Q17 The Venn diagram below shows the relationship between set M and set N. (ii) [1] ECZ-2012-P2-Q2(c)(ii) πΏππ π‘ π‘βπ π ππ‘ π΄′ ∪ π΅. [2] 11 ECZ-2012-P1-Q14 The Venn diagram below shows the number of elements in each region. Find n(A). 5 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 11 ECZ-2012-P1-Q4 The Venn diagram below shows the relationship between sets A and B. 16 List set A. A {1, 2, 4, 6, 7} B {2, 4, 6, 7} C {1, 6,7} D {6, 7} E {2, 4} Using set notation, describe the shaded region shown in the Venn diagram below. [2017.P1.Q4] 12(i) ECZ-2011-P2-Q2(d)(i) In a class of 50 pupils, 28 pupils like guava drink, 30 like apple drink and 10 like both. Illustrate this information in a Venn diagram. [2] (ii) ECZ-2011-P2-Q2(d)(ii) How many pupils do not like either of the drinks? [1] π΄ π΅ πΆ π· 13 ECZ-2011-P1-Q11 If G = {a, b, c, d, e}, how many subsets has set G? 14 π΄∩π΅ π΄′ ∩ π΅′ (π΄ ∪ π΅)′ (π΄ ∩ π΅)′ 17 [2017.P1.Q19] The Venn diagram below shows sets X and Y. ECZ-2011-P1-Q6 Given that E = {a, b, c, d, e, f, g, h, i, j, k} and A = {b, c, d, e, f, g, h}, find n(A'). A 11 B 7 C 4 D {b, c, d, e, f, g, h} E {a, i, j, k} 15. ECZ-2010-P2-Q5(d) Using set notation, describe the shaded region in the diagram below. [1] List the elements of X ∩ Y’. 18 πΊππ£ππ π‘βππ‘ πΈ = {π₯: 1 ≤ π₯ ≤ 14, π₯ ∈ π}, π΄ = {1, 3, 5, 7, 9}, π΅ = {1, 2, 3, 4, 6, 12}πππ 6 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, πΆ = {2, 3, 5, 11, 13}, [2017.P2.Q5(c)] (i) Illustrate this information in the Venn diagram below, [2] 2 EVALUATE – (INTEGERS, INDICES, REAL NUMBERS) 1 Evaluate √400. [2016.P1.Q15] 2 Find the value of 10 − (−3). [2016.P1.Q2] A −13 B −7 C 7 D 13 Which of the following is an irrational number? [2016.P1.Q4] A π B √4 3 C 4 (ii) Mathematics 8 - 9 0968-747007, 0955-747000 List the elements of π΄′ ∩ (π΅ ∪ πΆ) [2] 1.01 D [2015.P1.Q2] 2 + 42 3 πΉπππ π‘βπ π£πππ’π ππ π΄ 24 8 π΅ 14 πΆ 12 B √2 [2015.P1.Q24] 3 10 ECZ-2013-P1-Q26 πΊππ£ππ π‘βππ‘ π = −2 πππ π = −5, ππππ π‘βπ π£πππ’π ππ π2 + 2π. 7 √3 √5 C D √4 [2015.P1.Q14] πΊππ£ππ π‘βππ‘ π₯ = −2 πππ π¦ = 1, ππππ π‘βπ π£πππ’π ππ 4π₯ 2 − 3π₯π¦. πΉπππ π‘βπ π£πππ’π ππ √8 + √16 9 ECZ-2013-P2-Q1(a) 2 3 3 πΉπππ π‘βπ π£πππ’π ππ ( − ) ÷ . [3] 3 5 10 11 ECZ-2013-P1-Q23(a) πΈπ£πππ’ππ‘π 5 + (0.5)2 . 12 ECZ-2013-P1-Q21(a) πΉπππ π‘βπ π£πππ’π ππ 30 × 5 ÷ 50. 13 π· 6 [2015.P1.Q9] Which of the following is a rational number? A 7 5 [2015.P1.Q1]] Evaluate − 2 + (−8). A 10 B 6 C −6 D − 10 5 6 2 ECZ-2013-P1-Q14 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 2 1 + . 5 4 27 ECZ-2011-P1-Q1 Evaluate −2 − (−10). π΄ − 20 π΅ − 12 πΆ − 8 π· 8 πΈπ£πππ’ππ‘π 3.23 π + 47ππ + 5.1 π, πππ£πππ π¦ππ’π πππ π€ππ ππ πππ‘πππ . πΈπ£πππ’ππ‘π 14 ECZ-2013-P1-Q12 π΄ππππππ π‘βπ ππππππ€πππ ππ’πππππ ππ 1 πππ πππππππ πππππ: − 25, 0.5, , 2. 3 15 ECZ-2013-P1-Q4 Find the sum of the first four prime numbers. A 10 B 16 C 17 D 19 E 20 ECZ-2012-P2-Q7(a) 1 2 7 πΈπ£πππ’ππ‘π 2 × 1 ÷ 1 4 3 8 17 ECZ-2012-P2-Q2(a) 1 5 πΈπ£πππ’ππ‘π 1 ÷ [2] 4 6 28 2.5 D √3 29 Evaluate (−5) + (−3). [2017.P1.Q2] π΄ −8 π΅ −2 πΆ 2 π· 8 [2] 30 18 ECZ-2012-P1-Q26 Find the sum of the first 5 odd numbers. 19 ECZ-2012-P1-Q20(b) Find the exact value of 0.00002 × 30. 20 ECZ-2012-P1-Q19(b) Arrange the following numbers in descending order: −5, 0, 1, −2, −7. Find the value of (−4)2 + 23. [2017.P1.Q3] A 24 B 14 C −2 D −8 31 [2017.P1.Q16] πΊππ£ππ π‘βππ‘ π₯ = 3 πππ π¦ = −1, ππππ π‘βπ π£πππ’π ππ 21 ECZ-2012-P1-Q11 πΊππ£ππ π‘βππ‘ π = −2, π = −1 πππ π = 1, 2 ππππ π‘βπ π£πππ’π ππ π − ππ. 2π₯ 2 − 3π₯π¦. 32 [2017.P1.Q23] Find the value of 22 ECZ-2012-P1-Q6 Find the value of 18 − 3 × 2 + 4. A8 B 16 C 20 D 34 E 90 23 ECZ-2011-P2-Q8(b) Calculate the exact value of 88 ÷ 0.44 × 25. [2] 24 ECZ-2011-P2-Q3(d) πΉπππ π‘βπ π£πππ’π ππ 1.3 − 0.2 × 1.5 πΈ 12 Which of the following is an irrational number? [2017.P1.Q1] A 4.12 B √9 C 16 [2] 25 ECZ-2011-P2-Q1(b) 2 2 πΈπ£πππ’ππ‘π ÷ (1 + ) [3] 3 3 26 Mathematics 8 - 9 0968-747007, 0955-747000 ECZ-2011-P1-Q23(b) 8 3 √27 + √4 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 10 ECZ-2012-P1-Q10 Write 74 648 to the nearest 1 000. A 74 600 B 74 650 C 75 000 D 75 600 E 75 650 3 APPROXIMATION & ESTIMATION (SIGNIFICANT FIGURES & STANDARD FORM) 1 2 3 11 ECZ-2012-P1-Q3 How many significant figures has the number 0.4220? A1 B2 C3 D4 E5 How many significant figures are in the number 0.007020? [2016.P1.Q1] A 6 B 4 C 3 D 2 12 ECZ-2011-P1-Q25(a) During a football match between Zambia and Cameroon, 78 620 people attended the match. Express the number of people in standard form. [2016.P2.Q1(b)] Write 0.03568 in standard form correct to 2 significant figures. [2015.P1.Q3] Write 58.234 correct to one significant figure. A 5 B 6 C 58 D 60 4 [2015.P2.Q1a] Write 0.004289 in standard form correct to 2 decimal places. 5 ECZ-2013-P1-Q1 Express 4 520 to the nearest 1000. A 4 000 B 4 400 C 4 500 D 4 600 E 5 000 Mathematics 8 - 9 0968-747007, 0955-747000 13 ECZ-2011-P1-Q7 State the number of significant figures in 70.001. A 1 B 2 C 3 D 4 E 5 14 Round off 37.86 to the nearest tenth. [2017.P1.Q6] A 40 B 38 C 37.9 D 37.8 15 [2017.P2.Q1(a)] Express 0.0005426 standard form correct to 2 decimal places. 6 ECZ-2010-P1-Q5 The population of Zambia is about 11 894 200. Round off this number to the nearest thousand. A 12 000 000 B 11 896 000 C 11 894 000 D 11 893 000 E 11 000 000 7 ECZ-2013-P1-Q27 The population of a newly created district in 2012 was 12 699. Express this number in standard form correct to 3 significant figures. 8 ECZ-2013-P1-Q15(b) Express 58.74 cm to the nearest millimetre. 9 ECZ-2012-P1-Q16 Express 0.004219 in standard form correct to 3 significant figures. 9 in FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 4 SIMPLIFICATION π. ππππππππ¦ 2π‘ 2 − π‘ + 3π‘ 2 + 4π‘ [2016. π1. π30(π)] Call 0977-747000, 12 ECZ-2012-P1-Q9 Simplify 8π¦ + 2 − 3π¦. π΄ 8π¦ − π¦ π΅ 10π¦ − 3π¦ πΆ 5π¦ + 2 π· 10π¦ − 3 πΈ 11π¦ + 2 2 [2016.P1.Q8] π8 × π 3 ππππππππ¦ π3 13 ECZ-2011-P2-Q2(b) π+1 π πΈπ₯ππππ π + ππ π π πππππ πππππ‘πππ 2 3 ππ ππ‘π π ππππππ π‘ ππππ. [3] A π−5 π 3 B π−1 π 3 C π5 π 3 D π6 π 3 3 [2016. π2. π4π] ππππππππ¦ 2π₯ + 3(π₯ − 4) − 4π₯. 4 ππππππππ¦ 14 ECZ-2011-P2-Q2(a) ππππππππ¦ 2(π¦ − 3) − 3(2 − π¦). [2] 15 ECZ-2011-P1-Q16 π₯+3 π₯ πΈπ₯ππππ π − ππ π π πππππ πππππ‘πππ 3 5 ππ ππ‘π π ππππππ π‘ ππππ. [2015.P1.Q19] − 3π₯ + 2π¦ + π₯ − π¦. 16 ECZ-2011-P1-Q14(b) ππππππππ¦ 5π₯ + 2π¦ − π₯ − 2π¦. 5 ππππππππ¦ 6 [2015.P2.Q6a] 3π₯ + 7 − 2(π₯ − 3). ECZ-2013-P2-Q5(c) π¦+3 π¦−1 πΈπ₯ππππ π + ππ π π πππππ πππππ‘πππ 2 4 ππ ππ‘π π ππππππ π‘ ππππ. [3] 7 ECZ-2013-P1-Q3 ππππππππ¦ 5π₯ + 2π¦ − 6π₯ − 2π¦ + 2π₯. π΄ 17π₯π¦ π΅ π₯π¦ πΆ 2π₯ π· π₯ πΈ π¦ 17 ECZ-2011-P1-Q12 6π 2 − 24π ππππππππ¦ . 6π 18 ECZ-2011-P1-Q5 3 In the expression 2π₯π¦ + 5π₯ 2 + 4π¦, π₯ πππ π¦ πππ π£ππππππππ . State the coefficient of π¦. A 1 B 2 C 3 D 4 E 5 19 ππππππππ¦ 8 ECZ-2012-P2-Q8(c) 2 2 10π₯ π¦ 6π₯π¦ 4π¦ ππππππ¦ × 3 ÷ [3] 3π₯π¦ 2 5π₯ π¦ π₯ 9 Mathematics 8 - 9 0968-747007, 0955-747000 20 ππππππππ¦ ECZ-2012-P2-Q6(b) 2π 5 − 2π − ππ π π πππππ πππππ‘πππ 3 4 ππ ππ‘π π ππππππ π‘ ππππ. [3] πΈπ₯ππππ π 10 ECZ-2012-P2-Q4(b) ππππππππ¦ 2(5π − π) − 3(2π − 3π). [2] 11 ECZ-2012-P1-Q23 ππππππππ¦ 4π¦ 5 × 8π¦ 3 . 10 [2017.P1.Q18] 3a − 4b − 6a + b. [2017.P2.Q7(a)] 6π₯ + 4 − 3(5π₯ − 4). FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 5 Call 0977-747000, FRACTIONS, DECIMALS & PERCENTAGES 6 1 1. ECZ-2013-P1-Q23(b) A bus carried 52 pupils of whom 13 were girls. Express the number of boys as a fraction of the total number of pupils on the bus, in its lowest terms. 2 FACTORISATION Factorise completely. 24π₯ 2 + 72ππ₯ [2016.P1.Q16] [2015. π1. π11] πΉπππ‘ππππ π πππππππ‘πππ¦ 5ππ 2 − 10ππ. 3 ECZ-2013-P2-Q5(a) πΉπππ π‘βπ πΏπΆπ ππ 6ππ, 15π πππ 3ππ 2 . [2] 2 ECZ-2013-P1-Q13(a) Express 0.035 in percentage form. 3 ECZ-2013-P1-Q7 Express 9.5% as a decimal fraction. A 95.0 B 9.5 C 0.95 D 0.095 Mathematics 8 - 9 0968-747007, 0955-747000 4 ECZ-2013-P2-Q1(c) ππππππππ¦ 8π + 6π + 2π − 4π. [2] E 0.0095 5 ECZ-2013-P1-Q10 πΉπππ‘ππππ π πππππππ‘πππ¦ 3π + 18π2 . π΄ 3π(1 + 6π) π΅ 3π(1 + 9π) πΆ π(3 + 18π) π· 3(π + 9π2 ) πΈ 3π(π + 6π2 ) 4 ECZ-2012-P1-Q20(a) ABCD is a square. What fraction of the square is shaded? 6 ECZ-2012-P2-Q1(a) πΉπππ‘ππππ π πππππππ‘πππ¦ ππ − π 2 . [1] 7 πΉπππ‘ππππ π 8 5 ECZ-2012-P1-Q7 Express 0.16 as a fraction in its lowest terms. 4 1 10 16 16 π΄ π΅ πΆ π· πΈ 25 6 16 25 10 6 ECZ-2011-P1-Q14(a) Mwansa got 16 marks out of 25 in a Mathematics test. What percentage did she get in this test? 7 ECZ-2011-P1-Q8 Write 35% as a fraction in its lowest terms. 7 5 7 35 35 π΄ π΅ πΆ π· πΈ 20 20 50 50 100 11 ECZ-2011-P2-Q3(b) 4β2 − 12πβ. [2] [2017. π1. π11] πΉπππ‘ππππ π πππππππ‘πππ¦ 12π2 π − 10ππ 2 . FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 7 Call 0977-747000, Four orphans received help from Lugwasho Masiye Organisation for their education in the ratio 2:4:6:8. If the biggest amount was K2 400 000, calculate the total amount contributed by the organization. [3] RATIO & PROPORTION 1 Mr Chiyaka bought 3 bicycles at K2 100.00 for his workers. How much would he need if he wanted to buy 7 bicycles of the same type? [2016.P1.Q19] 10 ECZ-2011-P2-Q4(c) Mrs Gangu needs 4 people to do a piece of work in 12 days. How many people would she need to do the same work in 8 days? [3] 2 [2015.P1.Q26] In an election, 80 000 people voted. The votes that candidates A, B and C got were in the ratio 9:5:2 respectively. How many votes did candidate B receive? 11 ECZ-2011-P1-Q30 Timothy has twice as many sweets as Monde. If Timothy has 36 sweets, find the ratio of Timothy’s sweets to Monde’s sweets in its lowest terms. 3 ECZ-2013-P2-Q5(b) Nzala and Kachemba invested money in their business in the ratio 4:3 respectively. If they shared their profits according to the ratio of their investment, how much did Nzala get from a profit of K2 100.00? [2] 12 [2017.P1.Q7] Sepo and Thabo shared sweets in the ratio 5:3. If Thabo had 15 sweets, how many sweets did Sepo receive? A 9 B 10 C 25 D 75 4 ECZ-2013-P2-Q4(a) A boarding house had enough food to feed 30 boys for 5 days. If only 25 boys reported, how many days did the food last, if consumption per day was the same? [2] 5 ECZ-2013-P1-Q21(b) Express the ratio 9 g to 54 g in its simplest form. 6 ECZ-2013-P1-Q22 In a mixture of fruit juice, 25 litres was orange juice and 15 litres was mango juice. How many litres of orange juice would you expect in a mixture of 160 litres of fruit juice? 7 ECZ-2012-P2-Q8(b) The ratio of boys to girls in a Grade 9 class is 5:6 respectively. If there are 30 girls, find the total number of pupils in this class. [2] 8 ECZ-2012-P2-Q7(c) It takes 13 workers to do a piece of work in 14 days. How long will 26 workers take to complete the same piece of work, if they are working at the same rate? [2] 9 Mathematics 8 - 9 0968-747007, 0955-747000 ECZ-2011-P2-Q7(a) 12 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 8 Call 0977-747000, CHANGE SUBJECT OF THE FORMULA 9 1 [2016.P2.Q3b] π€+3 πΊππ£ππ π‘βππ‘ π₯ = , 2−π€ ππππ π€ π‘βπ π π’πππππ‘ ππ π‘βπ πππππ’ππ. 2 πΊππ£ππ π‘βππ‘ [2015.P2.Q1c] 2 Mrs Fwenyafwenya invested K860.00 at a rate of 7% simple interest per annum. After how many years is the interest going to be K301.00? [2016.P1.Q7] A 35 years B 7 years C 5 years D 4 years ππππ π π‘βπ π π’πππππ‘ ππ π‘βπ πππππ’ππ. ECZ-2013-P2-Q2(d) ππ₯ − π πΊππ£ππ π‘βππ‘ = π¦, π€ π π’πππππ‘ ππ π‘βπ πππππ’ππ. 4 ππππ π₯ π‘βπ [2] 3 ECZ-2012-P2-Q3(c) π , π−2 ππππ π π‘βπ π π’πππππ‘ ππ π‘βπ πππππ’ππ. SOCIAL & COMMERCIAL ARITHMETIC 1A sofa can be bought for K8 400.00 cash. It can also be bought on hire purchase by paying a deposit of K3 000.00 plus 10 equal monthly instalments of K800.00. Chiongeni wants to buy this sofa on hire purchase. How much more will she pay on hire purchase? [2016.P1.Q21] π + π 2= , 3 + ππ 3 Mathematics 8 - 9 0968-747007, 0955-747000 Kalota Primary School budgeted for K16 200.00 to renovate the school. The school raised 25% πΊππ£ππ π‘βππ‘ π = and applied for the rest of the amount from a bank. [3] How much did the school apply from the bank? 5 ECZ-2011-P2-Q5(a) Given that ππ = 4π + 3π, make m the subject of the formula. [3] [2016.P1.Q12] 4 6 Given that formula. [2017.P2.Q3(b)] β= salary of K24 480.00. What is his monthly gross salary 2π₯−4 3+π₯ [2016.P2.Q7c] Landila gets an annual , make π₯ the subject of the if his housing allowance is K400.00? [3] 5 [2016.P2.Q7d] Chiti is preparing to go to London. He has K19 600.00 to convert to British pounds. How much will he get if the exchange rate is £1= K9.80? 6 [2016.P2.Q8b ] A freezer costing K4 000.00 is depreciated using the straight line method at 5% per year. Find its book value after 4 years. 7 [3] [2016.P2.Q8c] Hanchito's wage for a 5 day working week is K360.00. Given that he works 8 hours per day, calculatate (i) his wage per year if there are 52 weeks in a year. (ii) his rate per hour. 13 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 8 Call 0977-747000, [2015.P1.Q17] Mr Kantwa deposited K6 000.00 14 [2015.P2.Q8b] Selula bought a cell phone for K1 380.00. How much is this amount in US dollars given that the exchange rate is $1 to K6.90? in a bank at the rate of 30% simple interest per annum for 9 months. Calculate the interest. 9 15 [2015.P1.Q25] 1 kg kapenta at K20.00 per kg, 2 packets of tomatoes at K10.00 per pack, 16 ECZ-2013-P1-Q25 The information below is the Munzi Water and Sewerage Company’s water tariffs: 2 heads of cabbage at K5.00 per head, 3kg of beans at K15.00 per kg. How much did she pay altogether? (ii) How much was her change? ECZ-2013-P2-Q8(a) Mrs Magoti bought a goat at K120.00 and sold it at K144.00. Calculate her percentage profit. [3] Chidoki had K100.00 to buy the following items: (i) Mathematics 8 - 9 0968-747007, 0955-747000 The first 60 litres are charged at K2.00 per litre. Anything above 60 litres is charged at K4.00 per litre. Mr Mema used 160 litres of water in June. What was his total bill for the month of June? 10 [2015.P2.Q1d] Kawombesha earns K7 000.00 per month. His income tax deductions are calculated as follows. 17 ECZ-2013-P1-Q18 A woman deposited K2 400.00 in her ZANACO bank account at the rate of 6% per annum for 12 months. Calculate the amount at the end of this period. 18 ECZ-2013-P1-Q13(b) An Airtime Scratch Card Dealer earns 10% commission from the sale of each card. Calculate the commission the dealer will earn from the sale of 150 scratch cards at K5.00 each. How much income tax does he pay? 19 ECZ-2012-P2-Q6(a) Mr Wailesi bought a radio for K500 000 and he later sold it for K650 000. Calculate the percentage profit. [2] 11 [2015.P2.Q3b] An agent sold a television set for K2 200.00. This amount includes 10% commission for the agent. What was the price of the TV set before the commission was added? 12 20 ECZ-2012-P2-Q4(c) Bridget earns K6 400 000 per month. She pays 25% of her earnings for water and electricity. She spends the remaining amount on food, school fees and transport in the ratio 4:3:1 respectively. Find the amount spent on food. [3] [2015.P2.Q6d] Kafola’s current salary is K5 000.00. He gets housing allowance at 20% of the salary. What amount will be his housing allowance after a salary increment of K750.00? 13 [2015.P2.Q8a] The insurance company rated the value of a house at K100 000.00. This value appreciates at the rate of 20% each year. Calculate its value after one year. 21 ECZ-2012-P2-Q2(d) A lady’s suit in Mrs Machipisa’s shop is priced at K450 000. During a sale, she sold it at 25% discount. Calculate the selling price. [3] 14 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 22 ECZ-2012-P2-Q3(a)(i) The table below shows the bus fare chart for local routes in Kafue town. Mathematics 8 - 9 0968-747007, 0955-747000 28 ECZ-2012-P1-Q18(a) Mrs Zimba bought 600 eggs and she discovered later that 90 eggs were broken. What percentage of the eggs were broken? 29 ECZ-2011-P2-Q5(b) Mr Amarenti, who owns a house valued at K36 000 000, wants to charge rent at 20% per annum of the value of the house. What monthly rent must he charge? [3] Chimuka and his three friends travelled from Kafue Estates to Turnpike. Find the total amount they paid. [1] 30 ECZ-2011-P2-Q1(c) Mrs Kaloba invested K900 000 in a bank for 3 years at 12% per annum. Calculate the interest she got after 3 years. [2] 23 ECZ-2012-P2-Q3(a)(ii) If they gave the conductor a K50 000 note, how much change did he give them? [1] 31 ECZ-2011-P1-Q29 Mubita invested K1 480 000 for 5 years and received an interest of K296 000. What was the rate of interest? 32 ECZ-2011-P1-Q27(i) Mrs Chikho bought the following items from Shoprite: 10 kg of beef at K12 000 per kg, 15 kg of sugar at K6 000 per kg, 3 tins of water paint at K20 000 per tin. Find the total bill for Mrs Chikho. 24 ECZ-2012-P1-Q29(b) Mr Kantemba sells lemons at K700 each. How many lemons did he sell if he had K105 000 at the end of the day? 25 ECZ-2012-P1-Q28 Mr Kalaba borrowed K2 500 000 from a commercial bank and paid K500 000 interest at a rate of 5% per annum. Find the time taken to repay the borrowed money. 33 ECZ-2011-P1-Q27(ii) If she was given 5% cash discount, how much did she pay for the items? 26 ECZ-2012-P1-Q22 Mrs Mwape bought the following items from a shop: 34 ECZ-2011-P1-Q20 A newspaper vendor receives a commission of K150 for each newspaper he sells. Find the commission he received after selling 940 newspapers. 3 tablets of soap at K4 000 each, 3 packets of sugar at K5 500 each, 2.5 litres of cooking oil at K34 000, 2 packets of washing powder at K9 500 each, 2 kilograms of bananas at K4 000 per kilogram. How much change did she get from K100 000? 35 [2017.P1.Q14] Calculate the simple interest on K360 000.00 invested at 12% per annum for 3 27 ECZ-2012-P1-Q21 Mwansa, Mwalukanga and Chodziwadziwa shared 60 mangoes. If Mwansa got 25 mangoes and Chodziwandziwa got 1 3 years. of the total number of mangoes, how many mangoes did Mwalukanga get? 15 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 36 Call 0977-747000, [2017.P1.Q25] Kasapato was given K150.00 10 CARTESIAN PLANE to buy the following items: 1 [2016.P2.Q3c] On the grid provided below, (π) ππππ‘ π‘βπ πππππ‘π π(−5, −5), π(−5, 1), π(−2, 3), π(1, 1) πππ π(1, −5) (ππ) ππππ π‘βπ πππππ‘π π‘π ππππ π ππππ¦πππ πππππ (πππ) ππππ€ π‘βπ ππππ π₯ = −2. 2kg sugar at K24.00 1 loaf of bread at K9.00 6 books at K35.00 2.5 litres of cooking oil at K39.00 37 (a) How much did he spend? (b) How much change did he receive? [2017.P2.Q4(b)] Mathematics 8 - 9 0968-747007, 0955-747000 A car was purchased at K24 000.00. Calculate the value of the car after 1 year, if depreciation for this period was 20%. 38 [2017.P2.Q5(a)] On a particular day, the exchange rate between the Zambian Kwacha and American dollar was $1 = K9.50. How many dollars could be exchanged for K28 500.00? 39 2 [2015.P2.Q5d] On the XOY - plane shown below, (i) State the co-ordinates of D, 1 (ππ) ππππ€ π‘βπ ππππβ ππ π¦ = π₯ 3 πππ π‘βπ ππππππ − 3 ≤ π₯ ≤ 6. [3] [2017.P2.Q6(b)] A salesman has a fixed monthly salary of K1 000.00. He receives a commission of 5% on all his sales. If the total sales for a year amounts to K320 000.00, calculate his annual income. 40 [2017.P2.Q8(b)] A woman's basic rate per hour is K5.00 and her overtime rate is 'time and a half’. If in a certain week she worked for 45 hours instead of 40 hours normal working hours, calculate her wage for that week. [3] 16 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 3(i) ECZ-2013-P2-Q6(c)(i) The XOY plane below shows a quadrilateral PQRS. In the XOY plane below, the points P, Q and R are (-4, -2), (-2, 4) and (4, 6), respectively. The three points P, Q and R are part of a rhombus PQRS. What is the name of the quadrilateral PQRS? Complete the rhombus by plotting the fourth point S. [1] (ii) ECZ-2011-P2-Q8(c)(ii) Write the coordinates of point S. [2] (iii) ECZ-2011-P2-Q8(c)(iii) Draw the lines of symmetry in this rhombus. [2] (ii) ECZ-2013-P2-Q6(c)(ii) Write the coordinates of the points P, Q and R. [3] 4(i) ECZ-2012-P2-Q8(a)(i) On the diagram below, plot the points P(1,2), Q(3,5), R(7,5), S(9,2) and join them in the same order. [3] 6 ECZ-2012-P1-Q1 How many lines of symmetry has a kite? A 4 B 3 C 2 D 1 E 0 7 [2017.P2.Q8(a)] (a) On the XOY plane below, (π) ππππ‘ π‘βπ πππππ‘π π΄(−2, −1), π΅(0, 1) πππ πΆ(2, 3), (ππ) ππππ€ π‘βπ ππππβ ππ π‘βπ π π‘ππππβπ‘ ππππ π¦ = π₯ + 2. (ii) ECZ-2012-P2-Q8(a)(ii) Name the shape formed in (i) above. [1] (iii) ECZ-2012-P2-Q8(a)(iii) Draw the line of symmetry of the shape PQRS. [1] 5(i) ECZ-2011-P2-Q8(c)(i) 17 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 11 FUNCTIONS 5 ECZ-2011-P2-Q6(c) 1 values of a and b in the arrow diagram below. A mapping from P to Q is such that π₯ The diagram below shows a mapping from set D to set R. [2016.P1.Q23] π₯ → 3. Find the [2] Find the value of π₯. 6 ECZ-2011-P1-Q19 πΌπ π‘βπ ππππππ‘πππ π¦ ∗ π₯ πππππ π¦ 2 − π₯, ππππ π‘βπ π£πππ’π ππ − 3 ∗ 2. 2 [2015.P1.Q27a] πΊππ£ππ π‘βππ‘ π(π₯) = 7 − 3π₯, ππππ π( −3). 7 [2017.P1.Q26] π₯+3 πΊππ£ππ π‘βππ‘ π(π₯) = , 2 3 [2015.P2.Q3a] Given the following set of ordered pairs (22, 11), (20, 10), (18, 9), (16, 8) and (14, 7), (I) find the function representing this mapping, (ii) find the value of x when y = −5. ππππ π(−7). 8 [2017.P2.Q3(c)] The arrow diagram below is a mapping from set P to set Q. 4 ECZ-2013-P2-Q7(c) A relation from set A to set B is given as: π₯ → 4 − π₯. Complete the arrow diagram below. [2] (π) πΌπ π₯ ∈ π πππ π¦ ∈ π, ππππ π‘βπ πππππ’ππ πππ π‘βππ πππππππ. [2] (ππ) πΉπππ π‘βπ π£πππ’π ππ π₯ π€βππ π¦ = 3. 18 [2] FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 12 SHAPES AND SYMMETRY 1 The figure below is a net of a ... [2016.P1.Q6] A B C D Cylinder Cone pyramid prism. A B C D E 2 How many faces has a triangular pyramid? [2016.P1.Q30(b)] 5 ECZ-2013-P1-Q5 How many lines of symmetry has the figure below? 3 [2015.P1Q8] How many faces does the solid below have? A 0 A B C D 3 2 1 uncountable cone cube. pyramid. prism. kite. B 1 C 2 D 3 E 5 6 ECZ-2012-P1-Q8 What is the order of rotational symmetry of the regular polygon shown below? 4 ECZ-2013-P1-Q9 The figure below is the net of a……………….. 19 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 13 POLYGONS 1 The interior angle of a regular polygon is 108°. How many sides does this polygon have? [2016.P1.Q17] 2 A 0 B 1 C 2 D 3 [2016.P2.Q4b] The angles of a quadrilateral are 3y°, (2y + 10)°, 4y° and y°. Find the E 5 value of y. 7 ECZ-2011-P1-Q10 State the order of rotational symmetry for the figure below. 3 [2016.P2.Q8a ] The sum of interior angles of a regular polygon is 1080°. Calculate the size of each interior angle. 4 [2015.P1.Q21] Find the size of each exterior angle of a regular hexagon. 5 [2015.P2.Q8c] Find the sum of the interior angles of a polygon with eight sides. 6 ECZ-2013-P2-Q7(a) The interior angles of a quadrilateral are x°, 2x°, 90° and 150°. Calculate the value of x. [3] A 8 B 4 C 2 D 1 E 7(i) ECZ-2013-P2-Q1(b)(i) The size of an interior angle of a regular polygon is 60°. Find the size of each exterior angle. [1] (ii) ECZ-2013-P2-Q1(a)(ii) Find the number of sides of this polygon. [1] 0 8 ECZ-2011-P1-Q9 How many faces does a triangular pyramid have? A 2 B 3 C 4 D 5 E 6 8 ECZ-2012-P2-Q5(a) What is the name of a polygon with 5 sides? 9 ECZ-2011-P1-Q2 State the number of lines of symmetry of the shape below. [1] 9(i) ECZ-2011-P2-Q3(a)(i) The size of an exterior angle of a regular polygon is 45°. Find the number of sides of this polygon. [1] (ii) ECZ-2011-P2-Q3(a)(ii) Calculate the sum of interior angles of this polygon. [2] 10 [2017.P1.Q21] Find the interior angle of a regular hexagon. A 1 B 2 C 3 D 4 11 [2017.P2.Q4(a)] Calculate the sum of interior angles of a 10 sided regular polygon. [2] E 6 20 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 5 [2015.P2.Q5c] In the triangular prism ABCDEF below, AC = 4cm, AB = 3 cm, BC = 5cm and BF = 11 cm. 14 MENSURATION 1 The mass of a sphere is 1.5kg. Find its volume if its density is 0.3g/cm3. [2016.P1.Q29] 2 [2016.P2.Q1(d)] Mr. Matanki bought a cylindrical tank to store drinking water. The tank has a height of 70cm and a radius of 20cm. Calculate its 22 volume. (Take π= ). 7 3 [2016.P2.Q7b] The diagram below shows a wooden triangular prism PQRSTU. Given that PQR=STU = 90°, PR = 10cm, PQ = 6cm. QR = 8cm and RU = 12cm, calculate the total surface area of the prism PQRSTU. Find its total surface area. 6 [2015.P2.Q6c] The diagram below shows a cylinder of radius 3.5cm and length 22cm. 22 (ππππ π = ) 7 Calculate its volume. 7(i) ECZ-2013-P2-Q7(b)(i) The diagram below shows the shape of Mr Mafamu’s garden. O is the centre of the semi-circle ADB. AB = 28m, BC = 14m and angle ABC = 90°. (Take π 4 [2015.P1.Q16] In a Woodwork practical, Jenipher cut a wooden block of length 15cm, breadth 10cm and height 6cm as shown below. = 22 7 ) Calculate the length ADB. [2] (ii) ECZ-2013-P2-Q7(b)(ii) Given that the area of the semi-circular part ABD is 308 m2, find the total area of Mr Mafamu’s garden. [3] Given that the density of the wooden block is 0.05g/cm3 , find its mass. 21 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 8(i) ECZ-2013-P2-Q2(c)(i) The figure below shows the shape of a room. 11 ECZ-2012-P1-Q27 A full tank holds 15 m3 of water. What is this capacity in litres? (1 cm3 = 1 ml). Find the area of the room. 12 ECZ-2012-P1-Q24 πΉπππ π‘βπ ππππ ππ π‘βπ π πππππππππ πππ£ππ πππππ€. 22 (π‘πππ π = ) 7 [2] (ii) ECZ-2013-P2-Q2(c)(ii) Calculate the cost of covering this room with a carpet, if the carpet is sold at K32.00 per square metre (m2). [2] 9 ECZ-2013-P1-Q15(b) Express 58.74 cm to the nearest millimetre. 7. ECZ-2013-P1-Q16 The area of a circle is 154 cm2. Calculate the length of its radius. (Take π = 13 ECZ-2011-P2-Q7(c) The figure below shows a semi-circle with diameter 14x cm. 22 ) 7 8. ECZ-2013-P1-Q14 πΈπ£πππ’ππ‘π 3.23 π + 47ππ + 5.1 π, πππ£πππ π¦ππ’π πππ π€ππ ππ πππ‘πππ . 9. ECZ-2012-P2-Q7(d) Find the surface area of a closed cylinder of base radius 7 cm and height 5 cm. (Take π = 22 7 ) [3] 9 ECZ-2012-P2-Q3(b) π΄ πππππ’πππ π βπππ‘ ππ πππ‘ππ βππ π πππππ’π ππ 14 ππ. 22 ππππππ π π‘π ππ , πππππ’πππ‘π ππ‘π πππππ’ππππππππ. [2] 7 10 ECZ-2012-P1-Q29(a) Find the perimeter of the figure below in terms of x. 22 22 , ππ₯ππππ π π‘βπ ππππ ππ π‘βπ 7 π πππ − ππππππ ππ π‘ππππ ππ π₯, πππ£πππ π¦ππ’π πππ π€ππ ππ ππ‘π π ππππππ π‘ ππππ. [2] ππππππ π π‘π ππ FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 14 ECZ-2011-P2-Q5(c)(i) The figure below shows a side view of a block of wood at Mr Timba’s workshop. The semi-circular part ABE is removed. BC = 10 cm and DC = 14 cm. Use π = Mathematics 8 - 9 0968-747007, 0955-747000 shown below. 22 7 Calculate the radius of the semi-circle ABE. [1] Given that the mass of the block is 385g, find its density 15 ECZ-2011-P2-Q5(c)(ii) Calculate the area of the shaded part. [3] 18 [2017.P1.Q30] A cylinder whose radius is 21cm has a curved surface area of 528cm2. Calculate 16 ECZ-2011-P1-Q21 The diagram below shows a rectangular swimming pool partly surrounded by a lawn 1m wide. The shaded part represents the lawn. The length of the swimming pool is 11m and the breadth is 7m. the height of the cylinder. [Take π as 22 7 ] 19 [2017.P2.Q2(d)] The figure PQRSTU below is a triangular prism. Given that RU = 20cm, PT = 6cm, TU = 8cm and QR = 10cm, find the surface area of the prism. [3] Find the perimeter of the lawn. 20 [2017.P2.Q7(c)] The diagram below is a cylinder of radius 5cm and height 7cm. 17 [2017.P1.Q20] The area of the base of a cylindrical block is 154cm2 and its height is 10cm as Calculate its volume. 23 [3] FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, C D 15 ANGLES 1 In the diagram below, AOB is a straight line, <BOD = 143°, <AOC = 57° and <BOE is a right angle. <AOC = 57° and <BOE is a right angle. 115° 65° 4 [2015.P1.Q28] In the diagram below, lines AB and CD are parallel. The line XY crosses AB and CD at P and Q respectively. R is on AB such that QR = RP = PQ. Find angle DQY. Find the sum of a and b. [2016.P1.Q8] 2 Mathematics 8 - 9 0968-747007, 0955-747000 5 [2015.P2.Q6b] The angles of triangle ABC are shown in the diagram below. In the diagram below, AB is parallel to CD, angle HEB = 50° and angle EGD = 110°. [2016.P1.Q27] Find angle FEG. Calculate the value of π₯. 3 [2015.P1.Q7] In the diagram below, BCD is a straight line, angle BAC = 50° and AB = AC. Find the angle ACD. A 130° B 6 ECZ-2013-P1-Q24 Triangle ABC below is an isosceles triangle in which AB = AC, angle BAC = 3x° and angle ABC = x°. Find the value of x. 120° 24 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 7 ECZ-2013-P1-Q15(a) In the diagram below, AB is parallel to DE, angle DCE =40° and angle CDE = 80°. A B C D E Find the size of angle ABC. 8(i) ECZ-2012-P2-Q5(d)(i) In the diagram below, PQ = QR, angle PQR = (x + 30)° and angle PRQ = (2x + 50)°. Find the value of x. 65° 75° 85° 90° 120° 10 ECZ-2012-P1-Q15 Find the size of each of the angles marked x and y in the diagram below. 11 ECZ-2012-P1-Q5 Given that an acute angle XOY in the diagram below is 45°, what is the size of the reflex angle XOY? [3] (ii) ECZ-2012-P2-Q5(d)(ii) Find the size of angle RPQ. [1] 9 ECZ-2013-P1-Q2 Find the value of x in the diagram below. A C E 12 25 45° 215° 315° B D 135° 225° ECZ-2011-P2-Q2(c)(i) FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, In the diagram below, QRS is a straight line, PR = RS, angle QRP = 50°, angle RSP = 25° and PQ = QR. Calculate angle QPR. [1] 13 Mathematics 8 - 9 0968-747007, 0955-747000 APQ= 130°. ECZ-2011-P2-Q2(c)(ii) Calculate angle PRS. [1] Find angle PQC. A 130° B 60° C 50° D 40° 14(i) ECZ-2011-P1-Q15(i) In the diagram below, ABC is a straight line, BD is parallel to CE, angle ABD = 75° and angle BDC = 45°. 17 [2017.P1.Q28] If x° and (3x - 2)° are complementary angles, find the value of x. 18 [2017.P2.Q7(b)] In the diagram below, ACE and BCD are straight lines, AB = AC, angle BAC = x° and angle DCE = (2x + 15)°. Find angle DCE. (ii) ECZ-2011-P1-Q15(i) Find angle BCD. 15 ECZ-2011-P1-Q4 In the diagram below, BDE is a straight line. Angle BCD = 70° and angle CDE = 150°. Calculate angle CBD. A 110° B 100° C 80° D 70° E Find the value of x 16 GEOMETRICAL CONSTRUCTION 55° 16 [2017.P1.Q9] In the diagram below, AB is parallel to CD and EF is a transversal. Angle 1 26 [2016.P2.Q5c] FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, (i) Construct triangle ABC in which AB = 4cm, BC = 5cm and AC = 6cm. (ii) Bisect the sides AB and AC and let them meet at O. (iii) With centre O and radius OA, draw a circle. Mathematics 8 - 9 0968-747007, 0955-747000 Using the point of intersection of these bisectors as the centre, draw a circle which touches all the three sides of triangle ABC. [1] 5(i) ECZ-2011-P2-Q4(b)(i) Use geometrical instruments to construct a triangle ABC with AB = 7.5 cm, BC = 9cm and AC = 8cm. [1] (ii) ECZ-2011-P2-Q4(b)(ii) Construct the bisectors of AB and BC, let the bisectors meet at O. [2] 2 [2015.P2.Q2c] (i) Construct triangle LMN in which LM = 7cm, MN = 5cm and LN = 6cm. (ii) Bisect angle LNM and angle LMN and label the point of intersection of the angle bisectors as O. (iii) Draw a perpendicular from O to the side LM. Label the point where the perpendicular meets LM as P. (iv) With O as the centre, draw a circle which touches all the three sides of the triangle LMN. (iii) ECZ-2011-P2-Q4(b)(iii) Taking OA as radius with centre O, construct a circle. [1] 6 3 (i) ECZ-2013-P2-Q4(b)(i) Use geometrical instruments to construct triangle XYZ in which XY = 8cm, angle XYZ = 60° and angle YXZ = 40°. [2] (ii) (iii) (ii) ECZ-2013-P2-Q4(b)(ii) Measure and write the length of XZ. [1] (iv) [2017.P2.Q4(c)] (i) Use geometrical instruments to construct triangle ABC in which AB = 4cm, BC = 5cm and AC = 6cm. [1] Measure and write the size of angle ABC. [1] Bisect the sides AB and BC and let the bisectors meet at O. [2] With centre O and radius OA, draw a circle which touches the vertices A, B and C. [1] (iii) ECZ-2013-P2-Q4(b)(iii) Construct the bisector of angle XZY. [1] (iv) ECZ-2013-P2-Q4(b)(iv) Construct the perpendicular bisector of YZ. [1] 4(i) ECZ-2012-P2-Q4(a)(i) Using Geometrical Instruments, construct triangle ABC in which AB = 9cm, BC = 7cm and AC = 6cm. [1] (ii) ECZ-2012-P2-Q4(a)(ii) Measure and write the size of angle ABC. [1] 17 STATISTICS (iii) ECZ-2012-P2-Q4(a)(iii) Construct the bisectors of angle CAB and angle ABC. [2] (iv) 1 A footballer scored the following number of goals: 1, 0, 2, 2, 0, 4, 2, 3, 1,2 in 10 matches. What was the median score? [2016.P1.Q10] ECZ-2012-P2-Q4(a)(iv) 27 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM A C 1 3 B D Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 2 4 2 The pie chart below shows colours that Grade 9 learners at Patapata Secondary School like. If 40 learners like blue, find the total number of Grade 9 learners at this school [2016.P1.Q25] 3 [2016.P2.Q4c] (i) How many games did the team play? (ii) Complete the frequency table below. A marketer made K200.00 profit from Kalembula, K150.00 profit from Chibwabwa and K250.00 profit from tomatoes. 4 [2015.P1.Q6] A girl scored 17, 43, 15, 22 Illustrate this information on the pie chart below. and 18 in Mathematics weekly tests. Find the mean score. A 23 B 22.8 C 18 D 15 5 [2015.P1.Q22] The bar chart below shows the distribution of the pupils’ shoe sizes in a grade 9 class. 4 [2016.P2.Q6c] The bar chart below shows the number of goals scored by a football team. 28 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 8 ECZ-2013-P2-Q6(b) The mean mass of 7 girls participating in a hundred metre race was 60kg. During the race, one girl whose mass was 54kg fainted. Find the mean mass of the remaining girls. [3] 9(i) ECZ-2013-P2-Q3(a)(i) The Pie chart below shows how Emma spent K 1 200.00. Find the number of pupils who wear size 5 and above. 6 [2015.P2.Q7c] The frequency table below shows the marks obtained by pupils in a Find the value of x. Mathematics test. [2] (ii) ECZ-2013-P2-Q3(a)(ii) How much did Emma spend on transport? [2] (i) What was the modal class? (iii) ECZ-2013-P2-Q3(a)(iii) Given that Emma spent K300.00 on groceries, what percentage of the total amount did she spend on groceries? 10 ECZ-2013-P2-Q3(c) Mr Kipuna made a profit of 20% after selling a chair at K60.00. Find the cost price of the chair. [2] (ii) Calculate the mean mark. 7 [2015.P2.Q8d] The compound bar chart below shows the number of bags of maize produced by Mr Hapopwe and Mr Milisi from 2010 to 2014. 11 ECZ-2013-P1-Q29 The bar chart below shows the production of sweet potatoes at Mwezi Farm Training Centre from 2005 to 2011. Find the difference in the total number of bags produced by the two farmers from 2010 to 2014. 29 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 14 ECZ-2012-P1-Q13 The frequency table below shows the number of goals Nyunya Football Club scored in a particular season. If their median score was 2.5, find the value of x. 15 ECZ-2012-P1-Q2 Bwalya played 9 games in a chess tournament and scored the following points; 3,2, 1, 0, 2, 1,4, 2, 0. What was her modal score? A0 B1 C2 D3 E4 How many tonnes of sweet potatoes were produced from 2006 to 2010? 12 ECZ-2013-P1-Q8 What is the median of 24, 18, 17, 16, 20, 30, 16? A 16 B 18 C 20 D 24 E 30 16(i) ECZ-2011-P2-Q6(a)(i) The table below shows the number of hectares for different crops grown by Mr Izyakulya. What fraction of the total number of hectares is Sorghum? [1] 13(i) ECZ-2012-P2-Q1(d)(i) A survey was conducted among 600 television viewers. The results are listed below. 240 enjoyed watching sports 160 enjoyed listening to music 150 enjoyed watching movies 50 enjoyed listening to news. Complete the table below which gives the angle of the sector that would represent each programme on a Pie chart. [3] (ii) ECZ-2011-P2-Q6(a)(ii) Use the information in the table above to complete the bar chart below. [4] (ii) ECZ-2012-P2-Q1(d)(ii) Use geometrical instruments to complete the Pie chart below. [2] 17 ECZ-2011-P1-Q18 The masses of 4 babies born on the same day were 3.1kg, 2.6kg, 3.3kg and 2.8kg. Calculate the average mass of the babies, giving your answer correct to the nearest kilogram. 18 30 ECZ-2011-P1-Q13 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, The average height of Nosiku, Naza, Twaambo and Natasha is 1.4 m. If Natasha’s height is 1.25m, what is the total height of the other three children? Mathematics 8 - 9 0968-747007, 0955-747000 Complete the pie chart below to illustrate this information. [4] 19 ECZ-2011-P1-Q3 From the word MATHEMATICAL, the modal letter is ……… A M. B A. C T. D L. E H. 20 [2017.P1.Q8] A netball team scored the following goals in seven games: 6, 3, 7, 2, 3, 5 and 10. What was the median score? A 3 B 5 C 6 D 10 23 [2017.P2.Q8(c)] The table below shows how Mwanga spends his time in a day. 21 [2017.P1.Q24] The marks scored in an English test by learners in a Grade 9 class are distributed as shown in the bar chart below. Activity No. of hours Relaxing Lessons Studying Sleeping 6 7 3 8 Use this information to complete the bar chart below. [3] How many learners scored more than five marks? 22 [2017.P2.Q6(c)] The favourite colours of 30 learners in a Grade 9 class are shown in the frequency table below. Colour Frequency Green 13 Blue 5 Red 8 18 NUMBER BASES Yellow 4 1 31 Convert 4.25 to a number in base 2. [2016.P1.Q13] FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 2 3 Call 0977-747000, [2016.P2.Q3a] Find the product of 432πππ£π and 23πππ£π , giving your answer in base five. Mathematics 8 - 9 0968-747007, 0955-747000 πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π π‘ππ. [2016.P2.Q7a] πΉπππ π‘βπ π£πππ’π ππ 1100π‘π€π ÷ 100π‘π€π , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π π‘π€π. 4 [2015.P1.Q23] πΆπππ£πππ‘ 11.011π‘π€π π‘π πππ π 10. [2] 15 [2017.P1.Q22] Convert 10.1112 to base 10. 16 [2017.P2.Q2b] πΈπ£πππ’ππ‘π 110110π‘π€π ÷ 110π‘π€π , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π π‘π€π. 17 [2017.P2.Q6(a)] Multiply 34five by 23five giving your answer in base five. [3] 5 [2015.P2.Q5a] πΈπ£πππ’ππ‘π 1111π‘π€π ÷ 11π‘π€π , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π π‘π€π. 7 [2015.P2.7b] ππ’ππ‘ππππ¦ 144πππ£π ππ¦ 13πππ£π , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π πππ£π. 8 ECZ-2013-P2-Q4(c) πΈπ£πππ’ππ‘π 31πππ£π × 11πππ£π , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π π‘ππ. [3] 9 ECZ-2013-P2-Q2(b) πΆπππ£πππ‘ 17π‘ππ π‘π π πππ π πππ£π ππ’ππππ. [2] 10 ECZ-2012-P2-Q5(b) πΉπππ π‘βπ π π’π ππ 531πππβπ‘ πππ 77πππβπ‘ , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π πππβπ‘. [2] 11 ECZ-2012-P2-Q1(c) πΆπππ£πππ‘ 1011π‘π€π π‘π πππ π 10. [2] 12 ECZ-2011-P2-Q8(a) Add 1101π‘π€π π‘π 1111π‘π€π and give your answer in base ten. [3] 13 ECZ-2011-P2-Q7(b) Calculate 32πππ£π × 14πππ£π giving your answer in base five. [2] 19 SEQUENCES 1 14 ECZ-2011-P2-Q1(a) πΉπππ 1022πππ£π − 212πππ£π , 32 The next two terms of the sequence 5, 9, 15, 23 are, A 33, 45. B 33, 39. FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM C D E Call 0977-747000, 33, 35. 25, 33. 25, 29. Mathematics 8 - 9 0968-747007, 0955-747000 that AB = 8km and AC = 10km, find the length of the road BC. [2016.P1.Q14] 2. ECZ-2013-P1-Q6 Find the next term in the sequence 5, 6, 8, 11, 15, ... A 20 B 19 C 18 D 17 E 16 3 ECZ-2012-P1-Q19(a) Find the next term in the sequence 1,2,4,7,11,16,…… 4. ECZ-2010-P2-Q3(a)(i) Write down the next term in each of the following sequences. 1, 4, 7, 10,______. [1] 2 [2015.P1.Q13] In the diagram below, BDC is a straight line. AD is perpendicular to BC, AB = AC = 13cm and BC = 10cm. 5. ECZ-2010-P2-Q3(a)(ii) Write down the next term in each of the following sequences. 1 1 2 2 20, 17 , 15, 12 , 10,______. [2] Find the length of AD. 3 ECZ-2013-P1-Q28 In the figure below, AB = 3 cm, BC = 4 cm, CD = 12 cm and angle ABC = angle ACD = 90°. Calculate the length of AD. 20 PYTHAGORAS’ THEOREM 4 ECZ-2012-P1-Q17 In the figure below, VWYZ is a square which is joined to a triangle XWY. XY = 15cm, VZ = 9cm and angle XWY = 90°. 1 The diagram below shows two straight roads AB and BC which join the main road at A and C. The road AB meets the road BC at right angles. Given 33 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 Find the length of BC. Calculate the length of VX. 5 ECZ-2011-P1-Q26 The diagram below shows a ladder 15 m long leaning against an upright wall of height w metres. The foot of the ladder is 9 m away from the wall. Find the height of the wall. 6 [2017.P1.Q13] In the diagram below, BCD is an isosceles triangle. BM is perpendicular to CD, BC = BD, BM = 12cm and CD = 10cm. 21 BEARINGS 1 An aircraft flies from A to B on a bearing of 120°. What bearing should it take to fly from B to A? [2016.P1.Q26] 2 [2015.P1.Q20] In the diagram below, the bearing of B from A is 120°. 34 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 22 EQUATIONS 1 Find the value of y in the equation 3y − 20 = 7. [2016.P1.Q11] 2 ππππ£π π‘βπ πππ’ππ‘πππ 3 ππππ£π π‘βπ πππ’ππ‘πππ Find the bearing of A from B. [2016.P2.Q1(a)] π₯ − 8 = 3(4 − π₯). [2015.P1.Q12] 2π₯ + 13 = 3. 4 [2015.P2.Q1b] ππππ£π π‘βπ πππ’ππ‘πππ 3(2π₯ + 1) = 17 − 2(π₯ − 1) 3 ECZ-2010-P1-Q12 In the diagram below, the bearing of P from Q is 080°. Find the bearing of Q from P. 5 ππππ£π π‘βπ πππ’ππ‘πππ ECZ-2013-P1-Q11 3 = 12. π 6 ECZ-2013-P1-Q30 Three children Akakulubelwa, Bubala and Chomba were given sweets. Akakulubelwa was given x sweets, Bubala was given 5 more than Akakulubelwa and Chomba had 10 more than Bubala. Express the number of sweets that Chomba got in terms of x, in its simplest form. 4 [2017.P1.Q15] The diagram below shows the bearing of Q from P which is 077°. 7 ECZ-2012-P2-Q1(b) ππππ£π π‘βπ πππ’ππ‘πππ 3(π¦ − 2) − 4 = 2. [2] 8 Solve the equation 2 3 = π π+2 Find the bearing of P from Q. 35 ECZ-2012-P1-Q25 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 9 ECZ-2011-P2-Q6(b) Solve the equation 3(π¦ − 2) = 4(9 − π¦). [3] 10 ππππ£π π‘βπ πππ’ππ‘πππ ECZ-2011-P1-Q24 3(π₯ − 5) = 45. 11 ππππ£π π‘βπ πππ’ππ‘πππ [2017.P1.Q12] 3(π₯ − 4) = 5 12 [2017.P2.Q2(a)] Solve the equation π₯ π₯ + =5 2 3 A B C B π₯≥2 π₯<2 π¦<2 π¦≥2 2 ππππ£π π‘βπ πππππ’ππ‘πππ [2016.P2.Q2(c)] 2(π₯ − 1) > 3π₯ − 5 3 ππππ£π π‘βπ πππππ’ππ‘πππ [2015.P1.Q29] 7 + 2π₯ > 5. 4 [2015.P2.Q4b] πΌπππ’π π‘πππ‘π π‘βπ π πππ’π‘πππ ππ π₯ + π¦ ≤ −2 ππ π‘βπ πππ − πππππ π βππ€π πππππ€, ππ¦ π βπππππ π‘βπ π€πππ‘ππ ππππππ πππ π‘βπ ππππππ − 5 ≤ π₯ ≤ 1. 23 INEQUATIONS 1 The diagram below shows the XOY plane with a shaded region. Which of the following inequalities describes the shaded region? [2016.P1.Q5] 5 ECZ-2013-P2-Q2(a) ππππ£π π‘βπ πππππ’ππ‘πππ π¦ − 4 < 5 + 3π¦. [2] 36 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 6 ECZ-2013-P1-Q19 ππππ£π π‘βπ πππππ’ππππ‘π¦ π − 4 > 3π + 8. 7 ECZ-2012-P2-Q2(b) ππππ£π π‘βπ πππππ’ππ‘πππ 3π₯ + 12 > 7π₯. [2] 8 ECZ-2012-P1-Q12 ππππ£π π‘βπ πππππ’ππ‘πππ 6π₯ − 13 > 11π₯ − 3. 9 ECZ-2011-P2-Q4(a) Solve the inequation π₯ − 3(π₯ − 2) > 2. [3] 10 ECZ-2011-P1-Q22 ππππ£π π‘βπ πππππ’ππ‘πππ 15 < − 4π₯ + 3. 11 [2017.P1.Q29] Solve the inequation 8 + 3π₯ > 2 12 [2017.P2.Q7(d)] Illustrate the solution of y ≥ x + 1 on the XOY plane shown below, by shading the wanted region, for the domain −3 ≤ x≤ 3. [3] 24 SIMULTENEOUS EQUATIONS 1 [2016.P2.Q2(b)] Solve the simultaneous equations 2π₯ − π¦ = 5, π₯ + π¦ = 4 2 [2015.P2.Q2(b)] Solve the simultaneous equations 3π₯ − 2π¦ = 12, π₯ + 3π¦ = −7 3 ECZ-2013-P2-Q6(a) Solve the simultaneous equations π₯ + π¦ = 0, 3π₯ − π¦ = −8. [3] 4 ECZ-2012-P2-Q7(b) Solve the following simultaneous equations 3π₯ + 4π¦ = 32, π₯ = 4π¦. [3] 5 37 ECZ-2011-P2-Q3(c) FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Solve the simultaneous equations π₯+π¦=1 3π₯ − π¦ = 7. Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 2 [2016.P2.Q6b] In the diagram below, triangles LMN and LPQ are similar. Given that LP = 6cm, PM = 3 cm, PQ = 4cm and NQ = 2cm, calculate the length of LQ. [3] 6 [2017.P2.Q1(c)] Solve the simultaneous equations [3] 2 π₯ + π¦ = 14, π₯ + π¦ = 4. 3 below. 25 SIMILARITY & CONGRUENCY [2015.P1.Q10] Study the diagrams 1 The diagram below shows two similar right- angled triangles ORS and OAB. Calculate, in (i) OR : AR, (ii) RS : AB. its lowest terms, the [2016.P1.Q22(i)] [2016.P1.Q22(ii)] Which of the triangles above are similar? A (i) and (ii) B (i) and (iii) C (ii) and (iii) D (ii) and (iv) ratio 4 [2015.P1.Q27b] In the diagram below, YZ is parallel to PQ, XY = 3cm, YP = 2cm and YZ = 5cm. 38 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 7 ECZ-2013-P2-Q8(d) In the figure below, AB = 12 cm, DE = 4 cm, CE = 5 cm and AB is parallel to DE. Find the ratio YZ : PQ. Find the length of BE. [3] 5 [2015.P1.Q30] The diagram below shows a parallelogram PQRS with its diagonals crossing at point O. 8 ECZ-2012-P2-Q3(d) In the diagram below, angle XPQ = angle XYZ = 90°, XQ = 15 cm, QZ = 10 cm, PQ = (x + 2) cm and YZ = (x + 6) cm. Name a pair of congruent triangles. 6 [2015.P2.Q3c] The triangles below are similar. Find the value of x. [3] 9 ECZ-2012-P1-Q18(b) The triangles below are similar. Which side corresponds to BC? Given that PQ = 18cm, QR = 20cm and XY = 30cm, calculate the length of WY. 39 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 12 [2017.P1.Q10] The diagram below shows a triangle ABC in which DE is parallel to BC. 10 ECZ-2011-P2-Q7(d) The triangles PQR and STV are similar. Angle PQR = angle STV, angle RPQ = angle VST and angle QRP = angle TVS. Find the value of x. Name one pair of corresponding sides. A AD and DB B DB and DE C AE and EC D AC and AE 13 [2017.P1.Q27] In the diagram below, AB is parallel to PQ. AB = 12cm, AP = 6cm and CP = 3cm. [3] 11 ECZ-2011-P1-Q23(a) The diagram below shows two similar triangles. Angle ACB = angle BED = 60° and angle CAB = angle BDE = 90°. Write the ratio CQ to CB in its lowest terms. 14 [2017.P2.Q1(d)] In the diagram below, ADB and AEC are straight lines. DE is parallel to BC, State the side that corresponds to BD. 40 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, DE = 1Ocm, BC = 15cm and BD = 4cm. Mathematics 8 - 9 0968-747007, 0955-747000 (i) state the order of matrix N, (ii) find 3N 5 [2015.P2.Q2a] πΈπ₯ππππ π ( 1 0 0 −2 ) ( ) ππ π π πππππ πππ‘πππ₯. 1 5 6 πΊππ£ππ π‘βππ‘ 1 π΄=( 3 [2015.P2.Q4c] 2 5 0 ) πππ π΅ = ( ), 1 0 6 ππππ π΄π΅. Calculate AD. 7 Given that P = (−4 1 2), [2017.P1.Q17] (a) state the order of matrix P, (b) find 4P. 8 πΊππ£ππ π‘βππ‘ 2 π΄=( 1 πΉπππ π‘βπ πππ‘πππ₯ π΄π΅. 9 πΊππ£ππ π‘βππ‘ π΄=( πΉπππ 2π΄ − π΅. 2 −3 [2017.P2.Q2c] 3 −1 2 ) πππ π΅ = ( ), 2 4 3 [3] [2017.P2.Q3a] 0 3 1 ) πππ π΅ = ( ), 5 4 −2 [3] 28 COMPUTER STUDIES 27 MATRICES 1 Name one output device. [2016.P1.Q28] 1 πβππ‘ ππ π‘βπ πππππ ππ πππ‘πππ₯ π· = ( [2016.P1.Q9] A 5 C 3×2 π B D πΊππ£ππ π‘βππ‘ π¨ = ( 1 2 3 4 1 )? 0 2 [2016.P2.Q4d] Given that the base of a triangle is b and its perpendicular height is h, complete the flow chart below, which is for calculating and displaying its area A. 6 2×3 12 4 1 −8 ) , ππππ π¨. 20 4 [2016. π1. π24] 3 5 πΈπ₯ππππ π ( −4 [2016.P2.Q1(c)] [3] 2 2 3 ) − 2( ) ππ π π πππππ πππ‘πππ₯ 3 3 2 4 πΊππ£ππ π‘βππ‘ πππ‘πππ₯ [2015.P1.Q15] π = (5 − 6 2), 41 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 3 A C Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 [2015.P1.Q5] Which of the following is an input device? Printer B Keyboard Monitor D Speaker 4 [2015.P2.Q7a] Given the length π and breadth π of a rectangle, write a simple program to calculate and output the area, A, of a rectangle. 5 Which symbol in the flow chart represents a decision stage? [2017.P1.Q5] 6 [2017.P2.Q5(b)] Given three numbers x, y and z, complete the flow chart below to calculate the mean (M) of the numbers. 29 PROBABILITY 42 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 1 [2016.P2.Q5a] A bag contains 15 white and 9 green balls. If a ball is picked at random from the bag, find the probability that it is green. Mathematics 8 - 9 0968-747007, 0955-747000 (STEP BY STEP SOLUTIONS) 2 [2015.P2.Q5b] A bag contains 6 red marbles and 3 blue marbles. A marble is picked at random from the bag, find the probability that it is blue. 1 1 (a) 3 [2017.P2.Q2(b)] A boy has 3 oranges and 5 lemons of the same size in a basket. Find the probability of randomly picking an orange from the basket. [2] SETS Set A ∪ B is a set of all elements found in set A and in set B. A ∪ B = {1, 2, 3, 4, 8} (b) First list the elements found in A’, then list the elements in B’. Complement of a set, A’, is a set of elements not found in a given set. A′ = {3, 5, 6, 7} π΅′ = {1, 5, 6, 7, 8} The intersection set of A complement and B complement is: A′ ∩ B ′ = {5, 6, 7} 2(i) Start by filling up what is common in all the three sets, i.e. 2. Then fill up the intersection of the pairs sets A and B, B and C and A and C. After that finish up each set. What is not found in all the sets remains outside in the Universal set E (9 in this case). (ii) First list the elements found in (π΄ ∪ π΅)′ , then list the elements in πΆ. Complement of a set, A’, is a set of elements not found in a given set. (π΄ ∪ π΅)′ = {3, 8, 9} πΆ = {2, 3, 5, 7, 8} The intersection set of (π΄ ∪ π΅) complement and set C is: (π΄ ∪ π΅)′ ∩ πΆ = {3, 8} ANSWERS 43 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 3 Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 First list the elements of π′ (elements not found in set P. π′ = {π, π, π, π, π, π} π = {π, π, π, π, β, π, π} Intersection set is what is found in both sets π′ ∩ π = {π, π, π} 4 A union B complement. πΈππππππ‘π πππ‘ πππ’ππ ππ (π΄ ∪ π΅) = (π΄ ∪ π΅)′ πΈ = {1, 2, 3, 4, 5, 6, 7, 8, 9} E is a set of natural numbers (N) that are less than 10. π = { 2, 3, 5, 7} π = {2, 4, 6, 8} π = {1, 2, 3, 6} Start by filling up what is common in all the three sets, i.e. 2. Then fill up the intersection of the pairs sets P and Q, Q and R and P and R. After that finish up each set. What is not found in all the sets remains outside in the Universal set E (9 in this case). 5(i) 7(i) Netball only = 23 − π₯ Volleyball only = 19 − π₯ Both netball and volleyball = π₯ πππ‘ππππ ππππ¦ + ππππππ¦ππππ ππππ¦ + πππ‘h = 30 23 − π₯ + 19 − π₯ + π₯ = 30 23 − π₯ + 19 = 30 23 + 19 − π₯ = 30 42 − π₯ = 30 −π₯ = 30 − 42 −π₯ = −12 −π₯ −12 = −1 −1 π₯ = 12 Netball only = 23 − π₯ Volleyball only = 19 − π₯ π₯ = 12 Netball only = 23 − π₯ = 23 − 12 = 11 Volleyball only = 19 − π₯ = 19 − 12 = 7 Pupils play one game only = 11 + 7 = 18 ππ’ππππ (ii) (π ∪ π )’ = πππππππ‘π πππ‘ πππ’ππ ππ π ∪ π (π ∪ π )’ = {4, 8, 9} π = {2, 4, 6, 8} Therefore, (π ∪ π )’ ∩ π = {4, 8} 6 . (P U Q)' means P U Q compliment. It is a set of elements not found in set (P U G). (P U Q)' (ii) 8 44 Set M’ is a set of elements NOT found in set M. Set M’ = {7, 9} FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 9 First fill the intersection set. 7 people had both umbrella and raincoat. We are given that 12 people had umbrellas. 7 of these 12 also had raincoats. Therefore, 12 – 7 = 5 people had umbrellas only. We are also given that 10 people had raincoats. Of these 10, 7 also had umbrellas. Therefore, 10 – 7 = 3 people had raincoats only. n(A) means the number of elements found in set A. n(A) = 11 + 3 = 14 11 (ii) (ii) Write the intersection set first. 10 pupils like both guava and apple drinks. This means that 18 people drink guava drink ONLY. 20 pupils drink apple drink ONLY. This gives us a total of 10 + 18 + 20 = 48. π(π΄ ∪ π΅)′ means the number of elements not found in (π΄ ∪ π΅). (π΄ ∪ π΅)′ = {π, π} π(π΄ ∪ π΅)′ = 2 This means that 50 − 48 = 2 pupils drink NEITHER guava nor apple drink. 13 ππ’ππππ ππ π π’ππ ππ‘π = 2π [π = ππ’ππππ ππ πππππππ‘π ππ π‘βπ π ππ‘] πβπππ πππ 5 πππππππ‘π ππ π ππ‘ πΊ ππ π(πΊ) = 5 ππ’ππππ ππ π π’ππ ππ‘π = 2π ππ’ππππ ππ π π’ππ ππ‘π = 25 ππ’ππππ ππ π π’ππ ππ‘π = 2 × 2 × 2 × 2 × 2 = 32 ππ’ππππ ππ π π’ππ ππ‘π = 32 π΄′ ∪ π΅ means elements not found in set A together with those found in set B. π΄′ = {π, π, π, π, π‘} π΅ = {π, π, π, π, π‘} π΄′ ∪ π΅ = {π, π, π, π, π, π, π‘} 14 11 Set A = {2, 4, 6, 7} All the elements inside set A. 12(i) Write the intersection set first. 10 pupils like both guava and apple drinks. This means that 18 people drink guava drink ONLY. 20 pupils drink apple drink ONLY. This gives us a total of 10 + 18 + 20 = 48. This means that 50 − 48 = 2 pupils drink NEITHER guava nor apple drink. Both umbrella and raincoat = 7 people Umbrellas only = 5 people Raincoats only = 3 people Neither umbrella nor raincoat = 24 − (7 + 5 + 3) = 24 − 15 = 9 ππππππ 10(i) Mathematics 8 - 9 0968-747007, 0955-747000 ECZ-2012-P1-Q14 45 E = {a, b, c, d, e, f, g, h, i, j, k} A = {b, c, d, e, f, g, h} A’ (A compliment) is the set of elements NOT found in set A. n(A') is the number of elements NOT found in set A. A’ = {a, i, j, k} Therefore, n(A')= 4. FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 15. (π΄ ∪ π΅)′ This is (A union B) complement. What is not found in A union B. 16 (π΄ ∩ π΅)′ π· This is (A intersection B) complement. What is not found in (A intersection B). 17 List the elements of X ∩ Y’. π = {π, π, π, π, π} π’ (ππ’π‘π πππ π) = {π, π, π, π, π} π ∩ π’ = {π, π, π} 18 (i) Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 1 √400 = √4 × 100 = √4 × √100 = 2 × 10 => 20 2 When two operators (−) or (+) are adjacent to each other (follow each other), multiply them to have one sign. (+) × (+) = (+) (−) × (−) = (+) (−) × (+) = (−) (+) × (−) = (−) Therefore, 10 − (−3) = 10 + 3 = 13 3 An Irrational Number is a real number that cannot be written as a simple fraction. It is irrational because it cannot be written as a ratio (or fraction), not because it is crazy! A Rational Number can be written as a Ratio of two integers (i.e. a simple fraction). Illustrate this information in the Venn diagram below, [2] π (Pi) is a famous irrational number. π =3.14159265358979323846264338 (and more...) You cannot write down a simple fraction that equals Pi. The popular approximation of 22 7 (ii) = 3.1428571428571... is close but not accurate. Another clue is that the decimal goes on forever without repeating. List the elements of π΄′ ∩ (π΅ ∪ πΆ) π΄′ = {2, 4, 6, 8, 10, 11, 12, 13, 14} π΅ ∪ πΆ = {1, 2, 3, 4, 5, 6, 11, 12, 13} π΄′ ∩ (π΅ ∪ πΆ) = {2, 4, 6, 11, 12, 13} 2 4 ππ , π‘βπππππππ, ππ‘ ππ πππ‘πππππ. 1 2 101 1.01 = πβπππππππ, ππ‘ ππ πππ‘πππππ. √4 = 2 = 100 4 2 [2015.P1.Q1]] Evaluate − 2 + (−8). A 10 B 6 C −6 D − 10 When two operators (−) or (+) are adjacent to each other (follow each other), multiply them to have one sign. (+) × (+) = (+) (−) × (−) = (+) (−) × (+) = (−) (+) × (−) = (−) EVALUATE 46 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Therefore, AS – Addition or Subtraction. These two rank equally, so just calculate from left to right, whichever comes first. Take note of the signs as you add and subtract. In short, after you have done "B" do "O", then "D", then "M". Then go from left to right doing any "A" or "S" as you find them. −2 + (−8) = −2 − 8 = −10 Use a number line to find −2 − 8 = −10 5 23 + 42 = 2 × 2 × 2 + 4 × 4 = 8 + 16 = 24 6 2 4 1 2 √4 = 2 = ππ 2 3 3 => ( − ) ÷ 3 5 10 5×2−3×3 3 => ÷ 15 10 10 − 9 3 => ÷ 15 10 1 3 => ÷ 15 10 1 10 => × 15 3 1 2 2 => × = 3 3 9 A Rational Number can be written as a Ratio of two integers (i.e. a simple fraction). An Irrational Number is a real number that cannot be written as a simple fraction. It is irrational because it cannot be written as a ratio (or fraction), not because it is crazy! Another clue is that the decimal goes on forever without repeating. 7 4π₯ 2 − 3π₯π¦ ππ’π‘ π‘βπ π£πππ’ππ π₯ = −2 πππ π¦ = 1 4 × (−2)2 − 3 × (−2) × 1 4 × (−2) × (−2) + 6 4×4+6 16 + 6 22 10 π2 + 2π ππ’π‘ π‘βπ π£πππ’ππ ππ π πππ π: π = −2 πππ π = −5. (−5)2 + 2(−2) (−5) × (−5) + 2 × (−2) 25 − 4 21 8 Cube root of a number is the number that you can multiply by itself 3 times to get a given number. The cube root of 8 is 2 because 2 × 2 × 2=8 11 5 + (0.5)2 5 + 0.5 × 0.5 5 + 0.25 5.25 3 √8 = 2 Square root is the number you multiply twice. √16 = 4 Mathematics 8 - 9 0968-747007, 0955-747000 πππππ’π π 4 × 4 = 16 3 12 Use BODMAS (Brackets Of (or Orders) Division Multiplication Addition Subtraction) to decide which operation to start with. B – Brackets first. O – Of or Orders (powers, indices (exponents), roots) D – Division M – Multiplication AS – Addition or Subtraction. These two rank equally, so just calculate from left to right, whichever comes first. Take note of the signs as you add and subtract. √8 + √16 = 2 + 4 = 6 9 Use BODMAS (Brackets Of (or Orders) Division Multiplication Addition Subtraction) to decide which operation to start with. B – Brackets first. O – Of or Orders (powers, indices (exponents), roots) D – Division M – Multiplication 47 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 In short, after you have done "B" do "O", then "D", then "M". Then go from left to right doing any "A" or "S" as you find them. => 30 × 5 ÷ 50 => 150 ÷ 50 => 3 In short, after you have done "B" do "O", then "D", then "M". Then go from left to right doing any "A" or "S" as you find them. 13 change from mixed to improper fraction 4×2+1 3×1+2 8×1+7 × ÷ 4 3 8 9 5 15 × ÷ 4 3 8 45 15 ÷ 12 8 π π π π π΅πππ: [ ÷ = × ] π π π π 45 8 × 12 15 3 2 × 3 1 2 Convert the cm to m. 47 π = 0.47 π 100 => 3.23 π + 47ππ + 5.1 π => 3.23 π + 0.47 π + 5.1 π Arrange the decimal points in a straight vertical line. A whole has a decimal point at the end. 3.23 π 0.47 π + 5.1 π_ 8.80 π_ 47 ππ = 14 Change the fraction 1 3 so that you can easily compare with 0.5. 1 = 0.33 3 1 < 0.5 3 In descending order we have 1 2, 0.5, , −25 3 to decimal 1 2 7 ×1 ÷1 4 3 8 2 17 1 5 1 ÷ 4 6 4×1+1 5 ÷ 4 6 5 5 ÷ 4 6 5 6 × 4 5 6 3 1 = =1 4 2 2 π π π π π΅πππ: [ ÷ = × ] π π π π 15 A prime number is a natural number that has two factors: 1 and the number itself. (1 is not a prime number because it has one factor only i.e. 1.) The first four prime numbers are: 2, 3, 5 and 7 2 + 3 + 5 + 7 = 17 16 Use BODMAS (Brackets Of (or Orders) Division Multiplication Addition Subtraction) to decide which operation to start with. B – Brackets first. O – Of or Orders (powers, indices (exponents), roots) D – Division M – Multiplication AS – Addition or Subtraction. These two rank equally, so just calculate from left to right, whichever comes first. Take note of the signs as you add and subtract. 18 An old number is a number which cannot be divided by 2 without leaving a remainder. The first 5 old numbers are 1, 3, 5, 7 and 9. Their sum is: 1 + 3 + 5 + 7 + 9 = 25 19 When you multiply two numbers, the number of decimal places in the answer (product) 48 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, is equal to the sum of the decimal places of both numbers. 0.00002 has 5 decimal places and 30 has 0 decimal places. The product 2 × 30 = 60 will have a total of 5 + 0 = 6 decimal places. The answer will be written as 0.00060 D – Division M – Multiplication AS – Addition or Subtraction. These two rank equally, so just calculate from left to right, whichever comes first. Take note of the signs as you add and subtract. In short, after you have done "B" do "O", then "D", then "M". Then go from left to right doing any "A" or "S" as you find them. 20 When two numbers appear on a number line, the number on the right side is greater than the number on its left side. 1, 0, −2, −5, −7. 88 ÷ 0.44 × 25 88 × 25 0.44 multiply the numerator and denominator by 100 to get rid of the decimal point. 88 × 100 × 25 0.44 × 100 8800 × 25 44 21 π 2 – ππ replace a, b and c with their values π = −2, π = −1 πππ π = 1 (−1)2 − (−2) × 1 1 − (−2) 1+2 3 200 × 25 5000 24 Use BODMAS (Brackets Of (or Orders) Division Multiplication Addition Subtraction) to decide which operation to start with. B – Brackets first. O – Of or Orders (powers, indices (exponents), roots) D – Division M – Multiplication AS – Addition or Subtraction. These two rank equally, so just calculate from left to right, whichever comes first. Take note of the signs as you add and subtract. In short, after you have done "B" do "O", then "D", then "M". Then go from left to right doing any "A" or "S" as you find them. 22 Use BODMAS (Brackets Of (or Orders) Division Multiplication Addition Subtraction) to decide which operation to start with. B – Brackets first. O – Of or Orders (powers, indices (exponents), roots) D – Division M – Multiplication AS – Addition or Subtraction. These two rank equally, so just calculate from left to right, whichever comes first. Take note of the signs as you add and subtract. In short, after you have done "B" do "O", then "D", then "M". Then go from left to right doing any "A" or "S" as you find them. 18 − 3 × 2 + 4 18 − 6 + 4 12 + 4 16 Mathematics 8 - 9 0968-747007, 0955-747000 1.3 − 0.2 × 1.5 (first multiply) 1.5 × 0.2 30 000____ 030___ When you multiply two numbers, the number of decimal places in the answer (product) is equal to the sum of the decimal places of both numbers. 23 Use BODMAS (Brackets Of (or Orders) Division Multiplication Addition Subtraction) to decide which operation to start with. B – Brackets first. O – Of or Orders (powers, indices (exponents), roots) 49 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 1.5 has 1 decimal place and 0.2 has 1 decimal place. The product 030 will have a total of 1 + 1 = 2 decimal places. The answer will be written as 0.30 Find the common denominator. (The number that can be divided by both 5 and 4.) 4×2+5×1 20 8+5 20 13 20 1.3 − 0.30 When subtracting or adding decimal numbers, arrange the decimal points in a straight vertical line. A whole has a decimal point at the end. 1.3 − 0.30___ 1.00 _ 1.3 − 0.30 = 1.00 27 Expand the brackets. [(−) × (−) = (+)] −2 − (−10) −2 + 10 = 8 28 D √3 An Irrational Number is a real number that cannot be written as a simple fraction. It is irrational because it cannot be written as a ratio (or fraction), not because it is crazy! A Rational Number can be written as a Ratio of two integers (i.e. a simple fraction). 25 Use BODMAS (Brackets Of (or Orders) Division Multiplication Addition Subtraction) to decide which operation to start with. B – Brackets first. O – Of or Orders (powers, indices (exponents), roots) D – Division M – Multiplication AS – Addition or Subtraction. These two rank equally, so just calculate from left to right, whichever comes first. Take note of the signs as you add and subtract. In short, after you have done "B" do "O", then "D", then "M". Then go from left to right doing any "A" or "S" as you find them. 2 3 2 3 2 3 2 3 2 3 2 5 Mathematics 8 - 9 0968-747007, 0955-747000 Another clue is that the decimal goes on forever without repeating. 3 6 ππ , π‘βπππππππ, ππ‘ ππ πππ‘πππππ. 1 2 412 4.12 = πβπππππππ, ππ‘ ππ πππ‘πππππ 100 25 2.5 = πβπππππππ, ππ‘ ππ πππ‘πππππ 10 √9 = 3 = 2 ÷ (1 + ) 3 3×1+1×2 ÷ 3 3+2 ÷ 3 5 π π π π ÷ [ ÷ = × ] 3 π π π π 3 × 5 .29 −8 When two operators (−) or (+) are adjacent to each other (follow each other), multiply them to have one sign. (+) × (+) = (+) (−) × (−) = (+) (−) × (+) = (−) (+) × (−) = (−) Therefore, (−5) + (−3) = −5 − 3 = −8 Use a number line to find −5 − 3 = −8 26 2 1 + 5 4 30 50 (−4)2 + 23 = −4 × −4 + 2 × 2 × 2 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 3 APPROXIMATION & ESTIMATION (SIGNIFICANT FIGURES & STANDARD FORM) = 16 + 8 = 24 31 πΊππ£ππ π‘βππ‘ π₯ = 3 πππ π¦ = −1, 2π₯ 2 − 3π₯π¦. 2(3)2 − 3(3)(−1) 2×9+9 1 27 Answer: B. 0.007020 has 4 s.f. Note Significant Figures (s.f.) – Rules 1) ALL non-zero numbers (1,2,3,4,5,6,7,8,9) are ALWAYS significant. 236 has 3 s.f. 236.5 has 4 s.f. 58149 has 5 s.f. 32 3 √27 = π‘βπ ππ’ππππ π€βππβ πππ£ππ 27 π€βππ ππ’ππ‘ππππππ ππ¦ ππ‘π πππ 3 π‘ππππ = 3 √4 = π‘βπ ππ’ππππ π€βππβ πππ£ππ 4 π€βππ ππ’ππ‘ππππππ ππ¦ ππ‘π πππ 2 π‘ππππ = 2 3 √27 + √4 = 3 + 2 = 5 51 2) ALL zeroes between non-zero numbers are ALWAYS significant. 20006 has 5 s.f. 2005 has 4 s.f. 5.09 has 3 s.f. 3) ALL zeroes which are SIMULTANEOUSLY to the right of the decimal point AND at the end of the number are ALWAYS significant. 0.00020 has 2 s.f. 3.500 has 4 s.f. 2.00 has 3 s.f. 4) ALL zeroes which are to the left of a written decimal point and are in a number ≥ 10 are ALWAYS significant. 20.0 has 3 s.f. 300.0 has 4 s.f. 5) The zero to the left of the decimal point on numbers less than one is NOT significant. 0.5 has 1 s.f. 6) Space holding zeros on numbers less than one are NOT significant. 0.0004 has 1 s.f. (the 3 zeros before 4 are space holding zeros) FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 7) 8) 2 Call 0977-747000, 100 has 1 s.f. 23000 has 2 s.f. Trailing zeros in a whole number are NOT significant. 20 has 1 s.f. 100 has 1 s.f. 23000 has 2 s.f. 4 Leading zeros in a whole number are NOT significant. 002 has 1 s.f. 015 has 2 s.f. [π¨ × 10π (πππππ πππ ππππ ) π¨ ππ π ππ’ππππ πππ‘π€πππ 1 πππ 10 (1 ≤ π΄ < 10). π ππ π‘βπ ππ’ππππ ππ ππππππ π‘βπ πππππππ ππππππ π‘βπ πππππππ πππππ‘ πππ£ππ π€βππ ππππππ π¨. ;Write 0.004289 in standard form. Move the decimal point until there is ONLY ONE nonzero significant figure (1, 2, 3, 4, 5, 6, 7, 8 or 9) on the left and multiply the resulting decimal number by 10 to the power n, where n is the number of places the decimal point moves. The sign of n is determined by the direction of movement of the decimal point. If the decimal point moves to the left, n will be positive (+). If the decimal point moves to the right, n will be negative (−). In this question, n = 3 and is negaitive. (πππππ πππ ππππ) π¨ × 10π π¨ ππ π ππ’ππππ πππ‘π€πππ 1 πππ 10 (1 ≤ π΄ < 10). π ππ π‘βπ ππ’ππππ ππ ππππππ π‘βπ πππππππ ππππππ π‘βπ πππππππ πππππ‘ πππ£ππ π€βππ ππππππ π΄. Write 0.03568 in standard form. Move the decimal point until there is ONLY ONE nonzero significant figure (1, 2, 3, 4, 5, 6, 7, 8 or 9) on the left and multiply the resulting decimal number by 10 to the power n, where n is the number of places the decimal point moves. The sign of n is determined by the direction of movement of the decimal point. If the decimal point moves to the left, n will be positive (+). If the decimal point moves to the right, n will be negative (−). In this question, n = 2 and is negaitive. 0.004289 in standard form is 0.004289 = 4.289 × 10−3 Round off 4.289 to 2 decimal places. The digit occupying the second decimal place is 8. Look at the digit to the right of 8: if it is 5 or greater, then you add 1 to 8. If it is less than 5, then do not do anything to 8, just write it down. In this case the number is 9, so we add 1 to 8. 0.004289 = 4.289 × 10−3 = 4.29 × 10−3 2 π. π. 0.03568 in standard form is 0.03568 = 3.568 × 10−2 5 To round off a number to the nearest 1 000: Step 1 Find the digit occupying the place value for thousands. (4 in this case) Step 2 Look at the digit just to the right of it. (to the right of 4 we have the digit 5.) Step 3 If that digit (5 in this case) is less than 5, do not change the rounding digit (4 in this case). If that digit (5 in this case) is = 5 or greater than 5, add 1 to the rounding digit (4 in this case). Step 4 Replace all digits to the right of the rounding digit (4 in this case) with zeros. Round off 3.568 To 2 significant figures The digit occupying the second significant figure position is 5. Look at the digit to the right of 5: if it is 5 or greater, then you add 1 to 5. If it is less than 5, then do not do anything to 5, just write it down. In this case the number is 6, so we add 1 to 5. 0.03568 = 3.568 × 10−2 = 3.6 × 10−2 2 π . π. Loot at question 1 solution for Significant Figures Rules 3 Mathematics 8 - 9 0968-747007, 0955-747000 60. Trailing zeros in a whole number are NOT significant. 20 has 1 s.f. 52 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, So, 4 520, rounded off to the nearest 1 000 will become 5 000 or greater, then you add 1 to 6. If it is less than 5, then do not do anything to 6, just write it down. In this case the number is 9, so we add 1 to 6. 12 699 = 1.2699 × 104 = 1.27 × 104 6 To round off a number to the nearest thousand: Step 1 Find the digit occupying the place value for thousands. (4 in this case) Step 2 Look at the digit just to the right of it. (to the right of 4 we have the digit 2.) Step 3 If that digit (2 in this case) is less than 5, do not change the rounding digit (4 in this case). If that digit (2 in this case) is = 5 or greater than 5, add 1 to the rounding digit (4 in this case). Step 4 Replace all digits to the right of the rounding digit (4 in this case) with zeros. 8 1 centimeter (cm) = 10 millimeters (mm) 58.74 ππ = 58.74 × 10 ππ = 587.4 ππ 587.4 mm to the nearest millimeter is 587 mm because the number to the right of 7 is less than 5. (If it was 5 or greater, then the answer would be 588 mm after adding 1 to 7.) 9 So, 11 894 200, rounded off to the nearest thousand will become 11 894 000 7 Mathematics 8 - 9 0968-747007, 0955-747000 π¨ × 10π (πππππ πππ ππππ ππ ππππππππ ππππππππ) π¨ ππ π ππ’ππππ πππ‘π€πππ 1 πππ 10 (1 ≤ π΄ < 10). π ππ π‘βπ ππ’ππππ ππ ππππππ π‘βπ πππππππ ππππππ π‘βπ πππππππ πππππ‘ πππ£ππ π€βππ ππππππ π΄. Write 0.004219 in standard form. Move the decimal point until there is ONLY ONE nonzero significant figure (1, 2, 3, 4, 5, 6, 7, 8 or 9) on the left and multiply the resulting decimal number by 10 to the power n, where n is the number of places the decimal point moves. The sign of n is determined by the direction of movement of the decimal point. If the decimal point moves to the left, n will be positive (+). If the decimal point moves to the right, n will be negative (−). In this question, n = − 3 and is negative. π¨ × 10π (πππππ πππ ππππ ππ ππππππππ ππππππππ) π¨ ππ π ππ’ππππ πππ‘π€πππ 1 πππ 10 (1 ≤ π΄ < 10). π ππ π‘βπ ππ’ππππ ππ ππππππ π‘βπ πππππππ ππππππ π‘βπ πππππππ πππππ‘ πππ£ππ π€βππ ππππππ π΄. Write 12 699 in standard form. Move the decimal point until there is ONLY ONE nonzero significant figure (1, 2, 3, 4, 5, 6, 7, 8 or 9) on the left and multiply the resulting decimal number by 10 to the power n, where n is the number of places the decimal point moves. The sign of n is determined by the direction of movement of the decimal point. If the decimal point moves to the left, n will be positive (+). If the decimal point moves to the right, n will be negative (−). In this question, n = 4 and is positive. 0.004219 in standard form is 0.004219 = 4.219 × 10−3 . Round off 4.219 To 3 significant figures The digit occupying the third significant figure position is 1. Look at the digit to the right of 1: if it is 5 or greater, then you add 1 to 1. If it is less than 5, then do not do anything to 1, just write it down. In this case the number is 9, so we add 1 to 1. 0.004219 = 4.219 × 10−3 = 4.22 × 10−3 12 699 in standard form is 12 699 = 1.2699 × 104 Significant Figures (s.f.) – Rules 1) ALL non-zero numbers (1,2,3,4,5,6,7,8,9) are ALWAYS significant. 236 has 3 s.f. Round off 1.2699 To 3 significant figures The digit occupying the third significant figure position is 6. Look at the digit to the right of 6: if it is 5 53 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 236.5 has 4 s.f. 58149 has 5 s.f. 2) ALL zeroes between non-zero numbers are ALWAYS significant. 20006 has 5 s.f. 2005 has 4 s.f. 5.09 has 3 s.f. 3) ALL zeroes which are SIMULTANEOUSLY to the right of the decimal point AND at the end of the number are ALWAYS significant. 0.00020 has 2 s.f. 3.500 has 4 s.f. 2.00 has 3 s.f. 4) Mathematics 8 - 9 0968-747007, 0955-747000 Find the digit occupying the place value for thousands. (4 in this case) Step 2 Look at the digit just to the right of it. (to the right of 4 we have the digit 6.) Step 3 If that digit (6 in this case) is less than 5, do not change the rounding digit (4 in this case). If that digit (6 in this case) is = 5 or greater than 5, add 1 to the rounding digit (4 in this case). Step 4 Replace all digits to the right of the rounding digit (4 in this case) with zeros. So, 74 648, rounded off to the nearest 1 000 will become 75 000 ALL zeroes which are to the left of a written decimal point and are in a number ≥ 10 are ALWAYS significant. 20.0 has 3 s.f. 300.0 has 4 s.f. 11 ECZ-2012-P1-Q3 How many significant figures has the number 0.4220? A1 B2 C3 D4 E5 5) The zero to the left of the decimal point on numbers less than one is NOT significant. 0.5 has 1 s.f. Solution 4 significant figures (s.f.) Rule number 1, 3 and 5 below apply. 6) Space holding zeros on numbers less than one are NOT significant. 0.0004 has 1 s.f. (the 3 zeros before 4 are space holding zeros) 12 π¨ × 10π (πππππ πππ ππππ ππ ππππππππ ππππππππ) π¨ ππ π ππ’ππππ πππ‘π€πππ 1 πππ 10 (1 ≤ π΄ < 10). π ππ π‘βπ ππ’ππππ ππ ππππππ π‘βπ πππππππ πππππ‘ πππ£ππ π€βππ ππππππ π΄. 7) Trailing zeros in a whole number are NOT significant. 20 has 1 s.f. 100 has 1 s.f. 23000 has 2 s.f. 8) Leading zeros in a whole number are NOT significant. 002 has 1 s.f. 015 has 2 s.f. Write 78 620 in standard form. Move the decimal point until there is ONLY ONE nonzero significant figure (1, 2, 3, 4, 5, 6, 7, 8 or 9) on the left and multiply the resulting decimal number by 10 to the power n, where n is the number of places the decimal point moves. The sign of n is determined by the direction of movement of the decimal point. If the decimal point moves to the left, n will be positive (+). If the decimal point moves to the right, n will be negative (−). In this question, n = 4 and is positive. To round off a number to the nearest 1 000: 78 620 in standard form is 78 620 = 7.8620 × 104 . 10 Step 1 54 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 8) Leading zeros in a whole number are NOT significant. 002 has 1 s.f. 015 has 2 s.f. 14 C (nearest tenth means 1 decimal place) (nearest hundredth means 2 decimal places) 13 5. Rule number 2 below applies Significant Figures (s.f.) – Rules 1) ALL non-zero numbers (1,2,3,4,5,6,7,8,9) are ALWAYS significant. 236 has 3 s.f. 236.5 has 4 s.f. 58149 has 5 s.f. 2) ALL zeroes between non-zero numbers are ALWAYS significant. 20006 has 5 s.f. 2005 has 4 s.f. 5.09 has 3 s.f. 3) ALL zeroes which are SIMULTANEOUSLY to the right of the decimal point AND at the end of the number are ALWAYS significant. 0.00020 has 2 s.f. 3.500 has 4 s.f. 2.00 has 3 s.f. 4) 5) 15 [2017.P2.Q1(a)] Express 0.0005426 in standard form correct to 2 decimal places. ALL zeroes which are to the left of a written decimal point and are in a number ≥ 10 are ALWAYS significant. 20.0 has 3 s.f. 300.0 has 4 s.f. π¨ × 10π (πππππ πππ ππππ ππ ππππππππ ππππππππ) π¨ ππ π ππ’ππππ πππ‘π€πππ 1 πππ 10 (1 ≤ π΄ < 10). π ππ π‘βπ ππ’ππππ ππ ππππππ π‘βπ πππππππ πππππ‘ πππ£ππ π€βππ ππππππ π΄. The zero to the left of the decimal point on numbers less than one is NOT significant. 0.5 has 1 s.f. 6) Space holding zeros on numbers less than one are NOT significant. 0.0004 has 1 s.f. (the 3 zeros before 4 are space holding zeros) 7) Trailing zeros in a whole number are NOT significant. 20 has 1 s.f. 100 has 1 s.f. 23000 has 2 s.f. Mathematics 8 - 9 0968-747007, 0955-747000 Write 0.0005426 in standard form. Move the decimal point until there is ONLY ONE nonzero significant figure (1, 2, 3, 4, 5, 6, 7, 8 or 9) on the left and multiply the resulting decimal number by 10 to the power n, where n is the number of places the decimal point moves. The sign of n is determined by the direction of movement of the decimal point. If the decimal point moves to the left, n will be positive (+). If the decimal point moves to the right, n will be negative (−). In this question, n = −4 and is negative. 0.0005426 in standard form is 0.0005426 = 5.426 × 10−4 = 5.43 × 10−4 . correct to 2 decimal places. 55 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 2π‘ 2 − π‘ + 3π‘ 2 + 4π‘ 2π‘ 2 + 3π‘ 2 + 4π‘ − π‘ 5π‘ 2 + 3π‘ 2 When dividing indices, subtract. 8 π = π8 ÷ π3 = π8−3 = π5 π3 π8 × π 3 = π8−3 × π 3 = π5 × π 3 = π5 π 3 π3 3 Multiply the bracket and group the like terms. 2π₯ + 3(π₯ − 4) − 4π₯ 2π₯ + 3 × π₯ − 3 × 4 − 4π₯ 2π₯ + 3π₯ − 12 − 4π₯ 2π₯ + 3π₯ − 4π₯ − 12 π₯ − 12 4 Group the like terms together. −3π₯ + 2π¦ + π₯ − π¦ −3π₯ + π₯ + 2π¦ − π¦ −2π₯ + π¦ Note. If you are not sure when adding or subtracting negative and positive numbers, use a number line (in your mind or by drawing it!) 5 Multiply the bracket and group the like terms. 3π₯ + 7 − 2(π₯ − 3) 3π₯ + 7 − 2 × π₯ − 2 × −3 3π₯ + 7 − 2π₯ + 6 3π₯ − 2π₯ + 7 + 6 π₯ + 13 6 π¦+3 π¦−1 + 2 4 find the common denominator 4 SIMPLIFICATION 2(π¦ + 3) + π¦ − 1 4 2π¦ + 6 + π¦ − 1 4 Group the like terms together. (Take note of the signs as you move the terms around, they should move with their sign. 56 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 2π¦ + π¦ + 6 − 1 4 3π¦ + 5 4 8π − 3 × 5 − 3 × −2π 12 8π − 15 + 6π 12 8π + 6π − 15 12 14π − 15 12 7 Group like terms together. 5π₯ + 2π¦ − 6π₯ − 2π¦ + 2π₯ 5π₯ − 6π₯ + 2π₯ + 2π¦ − 2π¦ π₯+0 π₯ 10 2(5π − π) − 3(2π − 3π) 2 × 5π − 2 × π − 3 × 2π − 3 × (−3π) 10π − 2π − 6π + 9π group like terms together 10π + 9π − 2π − 6π 19π − 8π 8 π΅πππ: Mathematics 8 - 9 0968-747007, 0955-747000 10π₯ 2 π¦ 6π₯π¦ 2 4π¦ × 3 ÷ 3π₯π¦ 2 5π₯ π¦ π₯ π π π π [ ÷ = × ] π π π π 10π₯ 2 π¦ 6π₯π¦ 2 π₯ × 3 × 3π₯π¦ 2 5π₯ π¦ 4π¦ multiply the indices ππ × ππ = ππ+π 10 × 6π₯ 2+1+1 π¦1+2 3 × 5 × 4π₯ 1+3 π¦ 2+1+1 11 Multiple the numbers and letters separately 4π¦ 5 × 8π¦ 3 4 × 8 × π¦5 × π¦3 32π¦ 5+3 32π¦ 8 when multiplying indices, you add them, when dividing you subtract them. π₯ π × π₯ π = π₯ π+π π₯ π ÷ π₯ π = π₯ π−π 60π₯ 4 π¦ 3 60π₯ 4 π¦ 4 π₯ 4π¦3 π₯ 4π¦4 π¦3 π¦×π¦×π¦ 1 = = π¦4 π¦ × π¦ × π¦ × π¦ π¦ 12 Group like terms together. 8π¦ + 2 − 3π¦ 8π¦ − 3π¦ + 2 5π¦ + 2 or divide the indices using ππ = ππ ÷ ππ = ππ−π ππ 13 π+1 π + 2 3 Find common denominator 3(π + 1) + 2 × π 6 3×π+3×1+2×π 6 3π + 3 + 2π 6 3π + 2π + 3 6 5π + 3 6 π₯ 4π¦3 = π₯ 4−4 π¦ 3−4 = π₯ 0 π¦ −1 = π¦ −1 π₯ 4π¦4 π₯0 = 1 1 π¦ −1 = π¦ 9 2π 5 − 2π − 3 4 2π × 4 − 3(5 − 2π) 12 57 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, ππππππππ¦ 3a − 4b − 6a + b. Group the like terms together. (Take note of the signs as you move the terms around, they should move with their sign. 3a − 4b − 6a + b 3a − 6a − 4b + b −3π − 3π 14 2(π¦ − 3) − 3(2 − π¦) expand brackets 2 × π¦ − 2 × 3 − 3 × 2 − 3 × −π¦ 2π¦ − 6 − 6 + 3π¦ Group like terms 2π¦ + 3π¦ − 6 − 6 5π¦ − 12 20 ππππππππ¦ πΈπ₯ππππ 15 π₯+3 π₯ − 3 5 find the common denominator 5 × (π₯ + 3) − 3 × π₯ 15 5π₯ + 5 × 3 − 3π₯ 15 5π₯ + 15 − 3π₯ 15 5π₯ − 3π₯ + 15 15 2π₯ + 15 15 5 1. Number [2017.P2.Q7(a)] 6π₯ + 4 − 3(5π₯ − 4). 6π₯ + 4 − 15π₯ + 12 6π₯ − 15π₯ + 4 + 12 −9π₯ + 16 FRACTIONS, DECIMALS & PERCENTAGES of boys = ππ’ππππ ππ ππ’ππππ − πππππ ππ’ππππ ππ πππ¦π = 52 − 13 ππ’ππππ ππ πππ¦π = 39 ππ’ππππ ππ πππ¦π 39 3 = = ππ’ππππ ππ ππ’ππππ 52 4 16 5π₯ + 2π¦ − π₯ − 2π¦ Group like terms together 5π₯ − π₯ + 2π¦ − 2π¦ 4π₯ + 0 4π₯ 2 To convert a decimal to a percent, multiply the decimal by 100, then add on the % symbol. An easy way to multiply a decimal by 100 is to move the decimal point two places to the right. 17 6π 2 − 24π 6π 0.035 ππ π πππππππ‘πππ = 0.035 × 100% = 3.5% 3 First factorise the numerator 6π(π − 4) 6π Divide 6π in numerator and denominator π−4 18 2π₯π¦ 3 + 5π₯ 2 + 4π¦ The coefficient of π¦ is 4. The coefficient of π₯ 2 is 5 The coefficient of π₯π¦ 3 is 2 19 Mathematics 8 - 9 0968-747007, 0955-747000 9.5 = 0.095 100 (Dividing a number by 100 results in the decimal point 9.5% = moving 2 steps to the left. Multiplying a number by 100 results in the decimal point moving 2 steps to the right.) 4 There are 3 half squares (shaded) out of a total of 8 half squares. [2017.P1.Q18] 58 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM πβπ πππππ‘πππ ππ Call 0977-747000, 3 8 Mathematics 8 - 9 0968-747007, 0955-747000 5ππ(π − 2) If you multiply the brackets, you should get the original expression. 5 Step 1: Write down the decimal divided by 1. 0.16 0.16 = 1 Step 2: Multiply both top and bottom by 10 for every number after the decimal point. (For example, if there are two numbers after the decimal point, then use 100, if there are three then use 1000, etc.) Since the number has 2 decimal places, we multiply numerator and denominator by 100. 0.16 100 => × 1 100 Step 3: Simplify (or reduce) the fraction. 16 => 100 divide numerator and denominator by 4. 4 => 25 3 πΏπΆπ ππ 6ππ, 15π πππ 3ππ 2 is the smallest number that can be divided by 6ππ, 15π πππ 3ππ 2 without leaving a remainder. The LCM for the numbers 6, 15 and 3 is 30 πβπ πΏπΆπ ππ ππ, π πππ ππ 2 ππ ππ 2 Therefore πΏπΆπ ππ 6ππ, 15π πππ 3ππ 2 ππ 30ππ 2 4 8π + 6π + 2π − 4π group like terms together 8π + 2π + 6π − 4π 10π + 2π 2(5π + π) 5 3π + 18π2 3 and m are common (factors) 3π(1 + 6π) 6 16 × 100% = 16 × 4% = 64% 25 6 ππ − π 2 π(π − π) 7 35 7 = 100 20 Divide 5 into 35 and 100. 35% = 7 4β2 − 12πβ 4β(β − 3π) 8 12π2 π – 10ππ 2 Take the common factors outside the brackets 2ππ(6π − 5π) 6 7 FACTORISATION RATIO & PROPORTION 1 Take the common factors outside the brackets 24π₯ 2 + 72ππ₯ 24π₯(π₯ + 3π) 1 if π πππ π are directly proportional (where one increases when the other increases and decreases when the other decreases), then π π1 = π π1 π€βπππ π1 πππ π1 πππ π‘βπ πππ€ π£πππ’ππ ππ π πππ π. 2 Take the common factor outside the brackets. 2 5ππ − 10ππ 3 7 = 2 100 π₯ 59 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 3 × π₯ = 2 100 × 7 Mathematics 8 - 9 0968-747007, 0955-747000 30 × 5 = 25 × π₯ 150 = 25π₯ 3π₯ = 14 700 150 25π₯ = 25 25 3π₯ 14 700 = 3 3 6=π₯ π₯ = πΎ4 900.00 π₯ = 6 πππ¦π 2 Note that if π πππ π are directly proportional (where one increases when the other increases and decreases when the other decreases), then π π1 = π π1 π1 πππ π1 πππ π‘βπ πππ€ π£πππ’ππ ππ π πππ π. πππ‘ππ πππ π΅ = π ππ‘ππ πππ π΅ × πππ‘ππ π£ππ‘ππ ππ’π ππ πππ πππ‘πππ πππ‘ππ πππ π΅ = 5 × 80 000 9+5+2 πππ‘ππ πππ π΅ = 5 × 80 000 16 5 9 g to 54 g 9:54 5 πππ‘ππ πππ π΅ = × 10 000 2 πππ‘ππ πππ π΅ = 9 54 : 9 9 1: 6 5 × 5 000 1 πππ‘ππ πππ π΅ = 25 000 6 The ratio of orange juice to mango juice in fruit juice is 25:15. π½π’πππ πππ‘ππ ππππππ ππ’πππ = × 160 πππ‘πππ ππ’π ππ πππ‘πππ 25 ππππππ ππ’πππ = × 160 πππ‘πππ 25 + 15 25 ππππππ ππ’πππ = × 160 πππ‘πππ 40 ππππππ ππ’πππ = 25 × 4 πππ‘πππ ππππππ ππ’πππ = 100 πππ‘πππ 3 The ratio is 4:3 Nzala gets: ππ§πππ πππ‘ππ × ππππππ‘ ππ’π ππ πππ‘πππ 4 × πΎ2 100 4+3 4 × πΎ2 100 7 7 ππππ πππ‘ππ × ππ’ππππ ππ ππ’ππππ π π’π ππ π‘βπ πππ‘πππ 4 × πΎ300 ππ’ππππ ππ πππππ = πΎ1 200 πΏππ‘ π₯ = ππ’ππππ ππ ππ’ππππ 6 30 = ×π₯ 5+6 6 30 = ×π₯ 11 6π₯ 30 = 11 30 × 11 = 1 × 6π₯ 330 = 6π₯ 330 6π₯ = 6 6 55 = π₯ 4 When the number of boys increases, the number of days the food will last decreases. When the number of boys decreases, the number of days the food will last increases. Therefore, this is inverse proportion. When π πππ π are inversely proportional, then π × π = π1 × π1 π1 πππ π1 πππ π‘βπ πππ€ π£πππ’ππ ππ π πππ π. 60 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, π₯ = 55 ππ’ππππ Mathematics 8 - 9 0968-747007, 0955-747000 do the work increases. Therefore, this is inverse proportion. When π πππ π are inversely proportional, then π × π = π1 × π1 π1 πππ π1 πππ π‘βπ πππ€ π£πππ’ππ ππ π πππ π. 8 When the number of workers increases, the number of days to do the work decreases. When the number of people decreases, the number of days to do the work increases. Therefore, this is inverse proportion. When π πππ π are inversely proportional, then π × π = ππ × ππ ππ πππ ππ πππ π‘βπ πππ€ π£πππ’ππ ππ π πππ π. 4 × 12 = π₯ × 8 48 = 8π₯ 48 8π₯ = 8 8 6=π₯ 13 π€ππππππ × 14 πππ¦π = 26 π€ππππππ × π₯ πππ¦π π₯ = 6 ππππππ 13 × 14 = 26 × π₯ 182 = 26π₯ Note that if π πππ π are directly proportional (where one increases when the other increases and decreases when the other decreases), then π π1 = π π1 π1 πππ π1 πππ π‘βπ πππ€ π£πππ’ππ ππ π πππ π. 182 26π₯ = 26 26 7=π₯ π = π π πππ Note that if π πππ π are directly proportional (where one increases when the other increases and decreases when the other decreases), then π π1 = π π1 π€βπππ π1 πππ π1 πππ π‘βπ πππ€ π£πππ’ππ ππ π πππ π. 11 Timothy to Monde 2π₯: π₯ 36: 18 36 2 = ππ 2: 1 18 1 9 The biggest amount, K2 400 000, is represented by 8 in the ratio. ππ’π ππ πππ π‘βπ πππ‘πππ = 2 + 4 + 6 + 8 ππ’π ππ πππ π‘βπ πππ‘πππ = 20 Let the total amount be π₯ 12 8 2 400 000 = 20 π₯ Let Sepo 5 π₯ = 3 15 receive π₯ sweets. Cross multiply 3 × π₯ = 5 × 15 8 × π₯ = 2 400 000 × 20 3π₯ = 5 × 15 8π₯ = 48 000 000 3π₯ 5 × 15 = 3 3 8π₯ 48 000 000 = 8 8 π₯ =5×5 π₯ = πΎ6 000 000 π₯ = 25 πππ‘ππ ππππ’ππ‘ = πΎ6 000 000 ππππ ππππππ£π 25 π π€πππ‘π 10 When the number of people increases, the number of days to do the work decreases. When the number of people decreases, the number of days to 8 CHANGE SUBJECT OF THE FORMULA 61 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 ππ₯ − π = π€π¦ 1 First, cross multiply π€+3 π₯= 2−π€ ππ₯ = π€π¦ + π ππ₯ π€π¦ + π = π π π€ + 3 = π₯(2 − π€) π₯= π€+3 =π₯×2−π₯×π€ π€ + 3 = 2π₯ − π€π₯ π€π¦ + π π 4 take all terms with w to one side, the rest to the π π−2 cross multiply π(π − 2) = π π×π−π×2=π ππ − 2π = π ππ − π = 2π π(π − 1) = 2π π(π − 1) 2π = π−1 π−1 2π π= π−1 π= other side. π€ + π€π₯ = 2π₯ − 3 factorise w π€(1 + π₯) = 2π₯ − 3 π€(1 + π₯) 2π₯ − 3 = 1+π₯ 1+π₯ 2π₯ − 3 3 − 2π₯ π€= ππ π€ = 1+π₯ −π₯ − 1 2 Cross multiply π + π 2= 3 + ππ 5 ππ = 4π + 3π (Put terms with ‘m’ in on one side of the equation.) 2(3 + ππ) = π + π ππ − 4π = 3π 2 × 3 + 2 × ππ = π + π π(π − 4) = 3π 6 + 2ππ = π + π π(π − 4) 3π = π−4 π−4 move all the terms with m to one side of the equation. The sign changes after crossing the equal π= sign. 3π π−4 2ππ − π = π − 6 factorise m 6 π(2π − 1) = π − 6 β= 2π₯ − 4 3+π₯ β 2π₯ − 4 = 1 3+π₯ π(2π − 1) π−6 = 2π − 1 2π − 1 π= π−6 2π − 1 cross multiply β(3 + π₯) = 2π₯ − 4 3 Solution ππ₯ − π =π¦ π€ 3β + βπ₯ = 2π₯ − 4 All terms containing x should be moved to one side of equal side. The rest should be moved to the other side. cross multiply 62 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 602π 3010 = 602 602 βπ₯ − 2π₯ = −3β − 4 Factorise x divide by 2 π₯(β − 2) = −3β − 4 π= π₯(β − 2) −3β − 4 = (β − 2) (β − 2) π₯= 1505 301 π = 5 π¦ππππ −3β − 4 (β − 2) 3 First find 25% of the amount. 9 25% ππ K16 200.00 SOCIAL & COMMERCIAL ARITHMETIC 25 × K16 200.00 = K4 050 100 The rest of the amount 1 K16 200 − K4 050 = πΎ12 150.00 Hire purchase bill = Deposit + Instalment × 10 = πΎ3 000 + πΎ800 × 10 = K3 000 + K8 000 = K11 000 Cash bill = πΎ8 400 4 ππππ‘βππ¦ ππππ π π πππππ¦ = ππππππ¦ + π΄ππππ€ππππ ππππ‘βππ¦ ππππ π π πππππ¦ = π·πππππππππ = K11 000 − πΎ8 400 = πΎ2 600 πΎ24 480 + πΎ400 12 ππππ‘βππ¦ ππππ π π πππππ¦ = πΎ2040 + πΎ400 ππππ‘βππ¦ ππππ π π πππππ¦ = πΎ2 440 2 Use the formula for simple interest. ππ π πΌ= 100 πΌ = ππππππ πΌππ‘ππππ π‘ = πΎ301 π = πππππππππ (ππππ‘πππ) π΄πππ’ππ‘ = πΎ860 π = πΌππ‘ππππ π‘ π ππ‘π = 7%, π = ππππ (ππππππ ππ π¦ππππ ) =? 5 £1 → πΎ9.80 π₯ → πΎ19 600 cross-multiply ππ π πΌ= 100 π₯ × πΎ9.80 = £1 × πΎ19 600 πΎ860 × 7 × π 100 86 × 7 × π 301 = 10 9.80π₯ = £19 600 πΎ301 = 9.80π₯ £19 600 = 9.80 9.80 cross multiply 301 × 10 = 86 × 7 × π π₯= £19 600 × 100 9.80 × 100 π₯= £19 60000 980 π₯= £196000 98 3010 = 602π 602π = 3010 divide both sides by 602 63 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 ππ π 100 πΎ6 000.00 × 30 × 0.75 πΌ= 100 πΎ135 000 πΌ= = K1 350 100 π₯ = £2000 πΌ= 6 π΅πππ π£πππ’π = πΆππ π‘ − π·ππππππππ‘πππ π΅πππ π£πππ’π = πΎ4 000 − 5 × πΎ4 000 × 4 π¦ππ 100 9 (π) π΄πππ’ππ‘ ππ ππππππ‘π = 1 × πΎ20 = πΎ20 π΅πππ π£πππ’π = πΎ4 000 − πΎ200 × 4 πππππ‘πππ = 2 × πΎ10 = πΎ20 π΅πππ π£πππ’π = πΎ4 000 − πΎ800 πΆππππππ = 2 × πΎ5 = πΎ10 π΅πππ π£πππ’π = πΎ3 200 π΅ππππ = 3 × πΎ15 = πΎ45 πππ‘ππ ππππ’ππ‘ = πΎ20 + πΎ20 + πΎ10 + πΎ45 πππ‘ππ ππππ’ππ‘ = πΎ95.00 7 (π) ππππ πππ π¦πππ = ππππππ¦ π€πππ × 52 π€ππππ (ππ) πΆβππππ = πΎ100 − πΎ95 = πΎ5 ππππ πππ π¦πππ = πΎ360 × 52 ππππ πππ π¦πππ = πΎ18 720 (ππ) π ππ‘π πππ βππ’π = 10 πβπ ππππ π‘ πΎ3 000 ππ πππ‘ π‘ππ₯ππ = πΎ0 ππππππ¦ π€πππ ππ’ππππ ππ βππ’ππ π ππ‘π πππ βππ’π = πΎ360 8 βππ × 5 πππ¦π π ππ‘π πππ βππ’π = πΎ360 40 βππ πβπ πππ₯π‘ πΎ1 000 ππ π‘ππ₯ππ ππ‘ 25% = 25 × πΎ1000 100 = πΎ250 πβπ πππ₯π‘ πΎ1 000 ππ π‘ππ₯ππ ππ‘ 30% = 30 × πΎ1000 100 = πΎ300 π ππ‘π πππ βππ’π = πΎ9 πππ βππ’π πβπ πππππππ ππ πΎ2000 ππ π‘ππ₯ππ ππ‘ 35% = 8 35 × πΎ2000 100 = πΎ700 Use the formula for simple interest. ππ π πΌ= 100 πππ‘ππ π‘ππ₯ ππππ = πΎ250 + πΎ300 + πΎ700 = πΎ1250 πΌ = ππππππ πΌππ‘ππππ π‘ =? 11 πππππ + πΆπππππ π πππ = πΎ2 200 π = πππππππππ (ππππ‘πππ) π΄πππ’ππ‘ = πΎ6 000.00 π = πΌππ‘ππππ π‘ π ππ‘π = 30%, π₯ + 10% ππ π₯ = πΎ2 200 9 π = ππππ (ππππππ ππ π¦ππππ ) = 9 ππππ‘βπ = 12 3 π = = 0.75 4 10 × π₯ = πΎ2 200 100 π₯ π₯+ = πΎ2 200 10 10π₯ + π₯ = πΎ2 200 10 π₯+ 64 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 11π₯ = πΎ2 200 10 Mathematics 8 - 9 0968-747007, 0955-747000 6.90π₯ $1 380 = 6.90 6.90 $1 380 × 100 π₯= 6.90 × 100 $138000 π₯= 690 $13800 π₯= 69 11π₯ = πΎ22 000 11π₯ πΎ22 000 = 11 11 π₯ = πΎ2 000 πππππππ πππππ ππππππ ππππππ π πππ = πΎ2 000 π₯ = $200 K1 380.00 = $200 12 πππ€ π πππππ¦ = πππ π πππππ¦ + πππππππππ‘ πππ€ π πππππ¦ = πΎ5 000 + πΎ750 πππ€ π πππππ¦ = πΎ5 750 15 π»ππ’π πππ πππππ€ππππ = 20% ππ πππ€ π πππππ¦ ππππππ‘ × 100% πΆππ π‘ πππππ π»ππ’π πππ πππππ€ππππ = 20% ππ πΎ5 750 πππππππ‘πππ ππππππ‘ = 20 × πΎ5 750 100 2 π»ππ’π πππ πππππ€ππππ = × πΎ5 75 1 (ππππππ‘ = πΎ120.00 − πΎ144.00 = πΎ24.00) π»ππ’π πππ πππππ€ππππ = πππππππ‘πππ ππππππ‘ = πΎ24.00 × 100% πΎ120.00 πππππππ‘πππ ππππππ‘ = 20% π»ππ’π πππ πππππ€ππππ = πΎ1 150.00 16 Mr Mema used 160 litres The first 60 litres are charged at K2.00 60 × πΎ2 = πΎ120 The remaining 160 − 60 = 100 πππ‘πππ are charged at K4.00 per litre. 100 × πΎ4 = πΎ400 13 To appreciate means to gain (increase) value. So the house increased in value by 20% after one year. ππππ’π = πΌπππ‘πππ π£πππ’π + 20% ππ ππππ‘πππ π£πππ’π π»ππ’π π π£πππ’π = πΎ100 000 + 20% ππ πΎ100 000 20 × πΎ100 000 100 2 π»ππ’π π π£πππ’π = πΎ100 000 + × πΎ100 00 1 π»ππ’π π π£πππ’π = πΎ100 000 + πππ‘ππ ππππ = πΎ120 + πΎ400 = πΎ520 17 π»ππ’π π π£πππ’π = πΎ100 000 + πΎ20 000 πΌ= π»ππ’π π π£πππ’π = πΎ120 000 ππ π 100 πΌ = ππππππ πΌππ‘ππππ π‘ =? 14 $1 → πΎ6.90 π = πππππππππ (ππππ‘πππ) π΄πππ’ππ‘ = πΎ2 400.00 π₯ → πΎ1 380 π = ππππ (ππππππ ππ π¦ππππ ) = 12 ππππ‘βπ = 1 π¦π π = πΌππ‘ππππ π‘ π ππ‘π = 6%, cross-multiply πΎ2 400.00 × 6 × 1 100 πΎ2 400 × 6 πΌ= 100 π₯ × πΎ6.90 = $1 × πΎ1 380 πΌ= 6.90π₯ = $1 380 65 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 25 × πΎ450 000 100 πππππππ πππππ = πΎ450 000 − 25 × πΎ4 500 πππππππ πππππ = πΎ450 000 − πΎ112 500 πππππππ πππππ = πΎ337 500 πΌ = πΎ144 πππππππ πππππ = πΎ450 000 − Amount at the end = πππππππππ + πΌππ‘ππππ π π΄πππ’ππ‘ ππ‘ π‘βπ πππ = πΎ2 400 + πΎ144 π΄πππ’ππ‘ ππ‘ π‘βπ πππ = πΎ2 544 22 The bus fare from Kafue Estates to Turnpike is K7 000 per person. There were 4 people. πππ‘ππ ππππ’ππ‘ = πΎ7 000 × 4 πππ‘ππ ππππ’ππ‘ = πΎ28 000 18 πππ‘ππ π ππππ = ππ’ππππ ππ πππππ × πππ π‘ πππ ππππ πππ‘ππ π ππππ = 150 × πΎ5 πππ‘ππ π ππππ = πΎ750 πΆπππππ π πππ = 10% 0π πΎ750 πΆπππππ π πππ = 23 πΆβππππ = πΎ50 000 − πΎ28 000 πΆβππππ = πΎ22000 10 × πΎ750 100 πΆπππππ π πππ = πΎ75 24 19 ππππππ‘ = πππππππ πππππ − πππ π‘ πππππ ππππππ‘ = πΎ650 000 − πΎ500 000 = πΎ150 000 ππππππ‘ πππππππ‘πππ ππππππ‘ = × 100% πΆππ π‘ πππππ πΎ150 000 πππππππ‘πππ ππππππ‘ = × 100% πΎ500 000 πΎ150 πππππππ‘πππ ππππππ‘ = % πΎ5 πππππππ‘πππ ππππππ‘ = 30% ππ’ππππ ππ ππππππ π πππ = πππ‘ππ πππ β πππ π‘ πππ πππππ ππ’ππππ ππ ππππππ π πππ = πΎ105 000 πΎ700 ππ’ππππ ππ ππππππ π πππ = 150 ππππππ 25 πΌ= ππ π 100 πΌ = ππππππ πΌππ‘ππππ π‘ = πΎ500 000 20 Subtract 25% of K6 400 000 25 × πΎ6 400 000 = πΎ1 600 000 100 π ππππππππ ππππ’ππ‘ = πΎ6 400 000 − πΎ1 600 000 π ππππππππ ππππ’ππ‘ = πΎ4 800 000 This amount is shared in the ratio food:school fees:transport in the ratio 4:3:1 Amount spent on food is represented by 4 in the ration 4:3:1 4 × πΎ4 800 000 4+3+1 4 × πΎ4 800 000 8 1 × πΎ4 800 000 2 πΎ2 400 000 π = πππππππππ (ππππ‘πππ) π΄πππ’ππ‘ = πΎ2 500 000 π = πΌππ‘ππππ π‘ π ππ‘π = 5%, π = ππππ (ππππππ ππ π¦ππππ ) =? 500 000 = πΎ2 500 000 × 5 × π 100 500 000 = πΎ25 000 × 5 × π 500 000 = 125 000π 500 000 125 000π = 125 000 125 000 4=T T = 4 years 26 3 tablets of soap at K4 000 each => 3 × πΎ4000 = π²ππ πππ 3 packets of sugar at K5 500 each 21 πππππππ πππππ = πΆππ π‘ πππππ − πππ πππ’ππ‘ πππππππ πππππ = πΎ450 000 − 25% ππ πΎ450 000 66 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, => 3 × πΎ5 500 = π²ππ πππ 2.5 litres of cooking oil at K34 000 => π²ππ πππ 2 packets of washing powder at K9 500 each => 2 × πΎ9 500 = π²ππ πππ 2 kilograms of bananas at K4 000 per kilogram => 2 × πΎ4 000 = π²π πππ Mathematics 8 - 9 0968-747007, 0955-747000 30 πΎ12 000 + πΎ16 500 + πΎ34 000 + πΎ19 000 + πΎ8 000 ππ π 100 πΌ = ππππππ πΌππ‘ππππ π‘ π = πππππππππ (ππππ‘πππ) π΄πππ’ππ‘ = πΎ900 000 π = πΌππ‘ππππ π‘ π ππ‘π = 12%, π = ππππ (ππππππ ππ π¦ππππ ) = 3 π¦ππππ πΎ900 000 × 12 × 3 πΌ= 100 πΎ89 500 πΌ = πΎ324 000 πΌ= Total cost ππππππ πΌππ‘ππππ π‘ = πΎ324 000 Change = πΎ100 000 − πΎ89 500 πΆβππππ = πΎ10 500 31 ππ π 100 πΌ = ππππππ πΌππ‘ππππ π‘ = πΎ296 000 π = πππππππππ π΄πππ’ππ‘ = πΎ1 480 000 π = πΌππ‘ππππ π‘ π ππ‘π =? π = ππππ (ππππππ ππ π¦ππππ ) = 5 π¦ππππ 1 480 000 × π × 5 296 000 = 100 27 First find how many mangoes Chodziwandziwa got. πΆβπππ§ππ€ππππ§ππ€π πππ‘ πΌ= 1 ππ π‘βπ π‘ππ‘ππ ππ’ππππ 3 1 × 60 = 20 πππππππ 3 Then find how many Mwalukanga got. Mwansa got 25. 60 − 25 − 20 15 πππππππ 7400000π 100 Cross multiply 296 000 = 7400000π = 296 000 × 100 28 πππππππ‘πππ ππ ππππππ = ππππππ ππππ × 100% π‘ππ‘ππ ππππ 7 400 000π = 29 600 000 7 400 000π 29 600 000 = 7 400 000 7 400 000 90 πππππππ‘πππ ππ ππππππ ππππ = × 100% 600 90 πππππππ‘πππ ππ ππππππ ππππ = × 1% 6 π =4 π = 4% πππππππ‘πππ ππ ππππππ ππππ = 15% 32 Cost of beef = πΎ12 000 × 10 = πΎ120 000 πΆππ π‘ ππ π π’πππ = πΎ6 000 × 15 = πΎ90 000 πΆππ π‘ ππ πππππ‘ = πΎ20 000 × 3 = πΎ60 000 πππ‘ππ ππππ = πΎ120 000 + πΎ90 000 + πΎ60 000 πππ‘ππ ππππ = πΎ270 000 29 Find 20% of K36 000 000. 20 × πΎ36 000 000 100 πΎ7 200 000 The tenant pays πΎ7 200 000 per annum (per year). Divide this amount by 12 to find the monthly rent. πΎ7 200 000 ππππ‘βππ¦ ππππ‘ = 12 33 πππ‘ππ ππππ = πΎ270 000. πΏππ π 5% πππ πππ’ππ‘ 5 5% ππ πΎ270 000 = × πΎ270 000 = πΎ13 500 100 πβπ ππππ πΎ270 000 − πΎ13 500 = πΎ256 500 ππππ‘βππ¦ ππππ‘ = πΎ600 000 67 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 π₯ → πΎ28 500.00 cross multiply 34 πππ‘ππ ππππππ π πππ = ππππππ π πππ × # ππ ππππππ = πΎ150 × 940 = πΎ150 × 940 πππ‘ππ ππππππ π πππ = πΎ141 000 9.5 × π₯ = 1 × 28 500.00 9.5π₯ 28500.00 = 9.5 9.5 π₯ = $3000 35 39 ππ π 100 πΌ = ππππππ πΌππ‘ππππ π‘ π = πππππππππ (ππππ‘πππ) π΄πππ’ππ‘ = πΎ360 000 π = πΌππ‘ππππ π‘ π ππ‘π = 12%, π = ππππ (ππππππ ππ π¦ππππ ) = 3 π¦ππππ πΎ360 000 × 12 × 3 πΌ= 100 πΌ= ππππππ¦ = πΎ1 000.00 πΆπππππ π πππ ππππππ£ππ = 5% ππ πΎ320 000.00 = 5 × πΎ320 000.00 100 = πΎ16 000.00 πππ‘ππ ππππππ = πΎ1 000.00 + πΎ16 000.00 πΌ = πΎ129 600 = πΎ17 000.00 ππππππ πΌππ‘ππππ π‘ = πΎ129 600 40 36 (a) A woman's basic rate per hour is K5.00 and her overtime rate is 'time How much did he spend? and a half’. If in a certain week she worked 2kg sugar at K24.00 = K24.00 1 loaf of bread at K9.00 = K9.00 6 books at K35.00 = K35.00 2.5 litres of cooking oil at K39.00 = K39.00 for 45 hours instead of 40 hours normal working hours, calculate her wage for that week. [3] ππππππ π€πππ = ππππππ βππ × πΎ5 TOTAL = K 107.00 (b) [2017.P2.Q8(b)] = 40 × πΎ5 = πΎ200 How much change did he receive? ππ£πππ‘πππ πππ¦ = ππ£πππ‘πππ βππ × πΎ5 × 1.5 Change = K150.00 – K107.00 = 5 βππ × πΎ5 × 1.5 = K43.00 = πΎ37.50 πππ‘ππ π€πππ = πΎ200 + πΎ37.50 37 The value of the car after 1 year, will reduce = πΎ237.50 (depreciate) by 20%. 10 CARTESIAN PLANE 24 000.00 − 20% ππ 24 000.00 20 24 000.00 − × 24 000.00 100 1 24 000.00 − 4 800 πΎ19 200.00 38 $1 → πΎ9.50 68 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 (i) (ii) 2 (i) The co-ordinates of D are (0,2). The first value is for π₯, the second is the value of π¦ at the given point. It is always (π₯, π¦). (ii) Find two points through which the line passes. (Pick reasonable values at random). The π₯ value picked must be within the given range −3 ≤ π₯ ≤ 6 1 π¦ = π₯ 3 π€βππ π₯ = 0, 1 (0,0) π¦ = × 0 => π¦ = 0 3 π€βππ π₯ = 3, 1 π¦ = ×3 3 => π¦ = 3 (3,1) Draw a line passing through (0,0) and (3,1) (iii) πβπ ππππ π₯ = −2 ππ π‘βπ π£πππ‘ππππ ππππ ππππ π πππ π‘βπ π₯ − ππ₯ππ ππ‘ π‘βπ πππππ‘ π€βπππ π₯ = −2. 69 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 3(i) Kite. A kite is a 4-sided flat shape that: • has two pairs of sides. • each pair is made of two adjacent sides that are equal in length. • Opposite angles in a kite are equal. The two diagonals are the lines of symmetry. (ii) When writing the coordinates of a point, start with the value of π₯ ππππππ€ππ ππ¦ π‘βπ π‘βπ π£πππ’π ππ π¦. It will appear as (π₯, π¦). π = (−2,2), π = (2,4), π = (6,2) 5(i) 4(i) (ii) Trapezium. A trapezium is a 4-sided flat shape with one pair of parallel sides. In the above shape, QR is parallel to PS. (iii) When a shape is folded along the line of symmetry, the two parts (two halves) match exactly (will cover each other completely). 70 (ii) The coordinates of S are (2,0) (iii) The rhombus has two lines of symmetry. FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 7 [2017.P2.Q8(a)] (a) On the XOY plane below, (π) ππππ‘ π‘βπ πππππ‘π π΄(−2, −1), π΅(0, 1) πππ πΆ(2, 3), (ππ) ππππ€ π‘βπ ππππβ ππ π‘βπ π π‘ππππβπ‘ ππππ π¦ = π₯ + 2. 6 1 line of symmetry. A kite is a 4-sided flat shape that: • has two pairs of sides. • each pair is made of two adjacent sides that are equal in length. Opposite angles in a kite are equal. The longer diagonal is the line of symmetry. (i) (x,y) The first number in the co-ordinate represents the value of x, the second the value of y. (ii) To draw π¦ = π₯ + 2, pick reasonable values of x at random and find y values. When x = 0, π¦ = 0 + 2 = 2 (0,2) πβππ π₯ = 3, π¦ = 3 + 2 = 5 (3,5) Draw a line passing through the points (0,2) and (3,5) 71 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 11 FUNCTIONS 1 π = 2π· + 5 π₯ = 2 × 11 + 5 π₯ = 22 + 5 π₯ = 27 2 The function π(π₯) is represented by 7 − 3π₯. π( −3) means putting −3 wherever there is π₯. π(π₯) = 7 − 3π₯ π(−3) = 7 − 3(−3) π(−3) = 7 − 3 × −3 π(−3) = 7 + 9 π(−3) = 16 5 π₯ πππππ π‘βππ‘ π π£πππ’π ππ π ππ ππππππ π‘π π 3 π£πππ’π ππ π ππ¦ πππ£πππππ ππ‘ ππ¦ 3. π = −1 3 π = −1 × 3 π = −π π₯→ 3 (i) The first number in a co-ordinate point represents x values while the second represents y values (π₯, π¦). In the question above, y values are half of x values. π₯ π₯ π(π₯) = ππ π¦= 2 2 6 =π 3 2=π π=π 6 π¦ ∗ π₯ = π¦2 – π₯ Replace π¦ with −3 and replace π₯ with 2 −3 ∗ 2 = (−3)2 − 2 = 9 − 2 =7 (ii) π(π₯) = −5 = π₯ 2 ππ π¦= π₯ 2 π₯ 2 −5 × 2 = π₯ 7 [2017.P1.Q26] π₯+3 πΊππ£ππ π‘βππ‘ π(π₯) = , 2 −10 = π₯ π₯ = −10 ππππ π(−7). π( −7) means putting −7 wherever there is π₯. π₯+3 π(π₯) = 2 (−7) + 3 π(−7) = 2 −4 π(−7) = 2 4 π₯ →4 − π₯ 2 →4 − 2=2 5 → 4 − 5 = −1 π(−7) = −2 72 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 8 (π) Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 Triangular prism. A triangular prism has two triangular bases at both ends and 3 rectangular surfaces on the other sides. π¦ =π₯−2 (ππ) π¦ = π₯ − 2 π€βππ π¦ = 3 3=π₯−2 3+2 =π₯ 5=π₯ π₯=5 12 SHAPES AND SYMMETRY 1 B 3 Cone 4 2 faces. The circular base and the cone (slanted) surface. Pyramid. Rectangular pyramid. A rectangular pyramid has a rectangular base and an apex (point) where the triangular surfaces meet. See diagram below. 2 A triangular pyramid has a triangular base and an apex (point) where the triangular surfaces meet. See diagram below. A triangular pyramid has 4 faces. Rectangular prism. Rectangular prism has two rectangular bases at both ends and 4 rectangular surfaces on the other sides. 73 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 7 Rotational symmetry is where you can turn an object so that it looks exactly the same. The number of positions in which it looks exactly the same gives you its order of symmetry. The order of rotational symmetry for the figure above is 2. (Rotating it to the upside down position, then rotate it back to its original position.) 8 4. A triangular pyramid has a triangular base and an apex (point) where the triangular surfaces meet. See diagram below. 5 5. When a shape is folded along the line of symmetry, the two parts (two halves) match exactly (will cover each other completely). The order of rotational symmetry and the number of lines of symmetry of any regular polygon is equal to the number of sides. The figure above is a regular polygon with 5 sides. Therefore, it has 5 lines of symmetry. Triangular pyramid. Triangular prism. Triangular prism has two Triangular bases at both ends and 3 rectangular sides. Triangular prism has 5 faces. 6 5. Rotational symmetry is where you can turn an object so that it looks exactly the same. The number of positions in which it looks exactly the same after rotating it gives you its order of symmetry. The order of rotational symmetry and the number of lines of symmetry of any regular polygon is equal to the number of sides. The order of rotational symmetry for the figure above (5 sides polygon or pentagon) is 5. 9 When a shape is folded along the line of symmetry, the two parts (two halves) match exactly (will cover 74 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 10π¦ = 350 each other completely). The shape has 1 line of symmetry as shown below. 10π¦ 350 = 10 10 π¦ = 35 3 Let us find the number of sides of the polygon using Sum of the interior angles of a polygon.. ππ’π ππ πππ‘πππππ ππππππ = 180°(π − 2) 1080° = 180°(π − 2) 1080 = 180π − 180 × 2 1080 = 180π − 360 1080 + 360 = 180π 1440 = 180π 13 POLYGONS 1440 180π = 180 180 1 ππ’ππππ ππ π ππππ = 8=π 360° πΈπ₯π‘πππππ πππππ π=8 πΈπ₯π‘πππππ πππππ = 180° − πππ‘πππππ πππππ ππ’ππππ ππ π ππππ = πΌππ‘πππππ πππππ = 360° 180° − πππ‘πππππ πππππ ππ’π ππ πππ‘πππππ ππππππ ππ’ππππ ππ π ππππ 1080 π 1080 πΌππ‘πππππ πππππ = 8 πΌππ‘πππππ πππππ = 360° 180° − 108° 360° ππ’ππππ ππ π ππππ = = 5 π ππππ 72° ππ’ππππ ππ π ππππ = πΌππ‘πππππ πππππ = 135° 2 Sum of the interior angles of a polygon is 180°(n − 2). A quadrilateral has 4 sides. ππ’π = 180°(π − 2) π = 4 π ππππ ππ’π = 180°(4 − 2) ππ’π = 180° × 2 ππ’π ππ π‘βπ πππ‘πππππ ππππππ = 360° 4 πΈπ₯π‘πππππ πππππ = 360° ππ’ππππ ππ π ππππ π΄ βππ₯ππππ βππ 6 π ππππ = π = 6 πΈπ₯π‘πππππ πππππ = 360° π Therefore, 3π¦° + (2π¦ + 10)° + 4π¦° + π¦° = 360° πΈπ₯π‘πππππ πππππ = 360° = 60° 6 3π¦ + 2π¦ + 10 + 4π¦ + π¦ = 360 Note 10π¦ + 10 = 360 3 sides – triangle 4 sides – Quadrilateral 10π¦ = 360 − 10 75 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 5 sides – pentagon 6 sides – hexagon 7 sides – heptagon 8 sides – octagon 10 sides – decagon 5 Mathematics 8 - 9 0968-747007, 0955-747000 Solution πΈπ₯π‘πππππ πππππ = ππ’π ππ π‘βπ πππ‘πππππ ππππππ = 180°(π − 2) π=8 ππ’π ππ π‘βπ πππ‘πππππ ππππππ = 180°(8 − 2) ππ’π ππ π‘βπ πππ‘πππππ ππππππ = 180° × 6 ππ’π ππ π‘βπ πππ‘πππππ ππππππ = 1 080° 360° ππ’ππππ ππ π ππππ ππ’ππππ ππ π ππππ = 360° πΈπ₯π‘πππππ πππππ ππ’ππππ ππ π ππππ = 360° 120° ππ’ππππ ππ π ππππ = 3 8 6 ECZ-2013-P2-Q7(a) The interior angles of a quadrilateral are x°, 2x°, 90° and 150°. Calculate the value of x. [3] 3 sides – triangle 4 sides – Quadrilateral 5 sides – pentagon 6 sides – hexagon 7 sides – heptagon 8 sides – octagon 10 sides – decagon 9(i) A regular polygon has all sides equal and all angles equal. 360° ππ’ππππ ππ π ππππ = πΈπ₯π‘πππππ πππππ 360° π= πΈπ₯π‘πππππ πππππ 360° π= 45° π=8 π = 8 π ππππ A polygon with 8 sides is called octagon. Solution Sum of interior angles in a quadrilateral is 360° π₯° + 2π₯° + 90° + 150° = 360° 3π₯° + 240° = 360° 3π₯° = 360° − 240° 3π₯° = 120° 3π₯° 120° = 3 3 π₯° = 40° π₯ = 40 3 sides – triangle 4 sides – Quadrilateral 5 sides – pentagon 6 sides – hexagon 7 sides – heptagon 8 sides – octagon 10 sides – decagon 7(i) ECZ-2013-P2-Q1(b)(i) The size of an interior angle of a regular polygon is 60°. Find the size of each exterior angle. [1] Solution πΏππ‘ ππ₯π‘πππππ πππππ = π₯. ππ₯π‘πππππ πππππ + πππ‘πππππ πππππ = 180° π₯ + 60° = 180° π₯ = 180° − 60° π₯ = 120° (ii) Sum of the interior angles of a polygon is 180°(n − 2). ππ’π = 180°(π − 2) π = 8 π ππππ ππ’π = 180°(8 − 2) ππ’π = 180° × 6 (ii) ECZ-2013-P2-Q1(b)(ii) Find the number of sides of this polygon. [1] 76 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, ππππ’ππ ππ π πΆπ¦ππππππ = π½ = π ππ π π€βπππ π = πππππ’π πππ β = βπππβπ‘ ππ’π ππ π‘βπ πππ‘πππππ ππππππ = 1080° 10 Hexagon has 6 sides. 360° πΈπ₯π‘πππππ πππππ = ππ’ππππ ππ π ππππ πΈπ₯π‘πππππ πππππ = Mathematics 8 - 9 0968-747007, 0955-747000 π = ππ 2 β 360° 6 π = 20ππ πππ β = 70ππ 22 × (20ππ)2 × 70ππ 7 πΈπ₯π‘πππππ πππππ = 60° π= πΈπ₯π‘πππππ πππππ + πππ‘πππππ πππππ = 180° π = 22 × 400ππ2 × 10ππ πΌππ‘πππππ πππππ = 180° − πΈπ₯π‘πππππ πππππ π = 88 000ππ3 πΌππ‘πππππ πππππ = 180° − 60° πΌππ‘πππππ πππππ = 120° 11 [2017.P2.Q4(a)] Calculate the sum of interior angles of a 10 sided regular polygon. [2] ππ’π = 180°(π − 2) π = 10 π ππππ ππ’π = 180°(10 − 2) ππ’π = 180° × 8 ππ’π ππ π‘βπ πππ‘πππππ ππππππ = 1440° 14 MENSURATION 1 π·πππ ππ‘π¦ = πππ π ππππ’ππ ππππ’ππ = πππ π 1.5ππ = 0.3π π·πππ ππ‘π¦ ππ3 change kg to g ππππ’ππ = 1500π ππ3 0.3π ππππ’ππ = 1500 × 10 3 ππ 0.3 × 10 3 15000 3 ππππ’ππ = ππ = 5 000 ππ3 3 A triangular prism has two triangular bases at both ends and 3 rectangular surfaces on the other sides. Therefore, total surface area is the sum of the area of the 3 rectangles and 2 triangles. 2 77 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, π¨πππ ππ π πππππππππ = π × π π΄πππ ππ π΅πΆπ·πΉ = 11 × 5 = 55 ππ2 π΄πππ ππ π΄πΆπ·πΈ = 11 × 4 = 44 ππ2 π΄πππ ππ π΄π΅πΉπΈ = 11 × 3 = 33 ππ2 π π¨πππ ππ π ππππππππ = × π × π π 1 π΄πππ ππ π΄π΅πΆ = × 3 × 4 = 6 ππ2 2 1 π΄πππ ππ π·πΈπΉ = × 3 × 4 = 6 ππ2 2 πππ‘ππ ππππ = 55 + 44 + 33 + 6 + 6 ππ2 πππ‘ππ ππππ = 144 ππ2 π¨πππ ππ π πππππππππ = π × π π΄πππ ππ πππ π = 12 × 10 = 120 ππ2 π΄πππ ππ ππππ = 12 × 6 = 72 ππ2 π΄πππ ππ πππ π = 12 × 8 = 96 ππ2 π π¨πππ ππ π ππππππππ = × π × π π 1 π΄πππ ππ πππ = × 6 × 8 = 24 ππ2 2 1 π΄πππ ππ ππ π = × 6 × 8 = 24 ππ2 2 πππ‘ππ ππππ = 120 + 72 + 96 + 24 + 24 ππ2 πππ‘ππ ππππ = 336 ππ2 6 [π = πππ π ππππ × βπππβπ‘] π = ππ 2 β π = π£πππ’ππ, π = πππππ’π = 3.5 ππ, β = βπππβπ‘ = 22 π π = ππ 2 β 4 π·πππ ππ‘π¦ = Mathematics 8 - 9 0968-747007, 0955-747000 πππ π ππππ’ππ 22 × (3.5)2 × 22 7 22 π= × 0.5 × 3.5 × 22 1 22 π= × 3.5 × 11 1 π= πππ π = π·πππ ππ‘π¦ × ππππ’ππ ππππ’ππ = π × π × β = 15 × 10 × 6 = 900 ππ3 , π·πππ ππ‘π¦ = 0.05π/ππ3 πππ π = π·πππ ππ‘π¦ × ππππ’ππ π = 847 ππ3 πππ π = 0.05π/ππ3 × 900 ππ3 πππ π = 35π 5 7(i) ADB is the circumference of the semicircle with diameter π = 28 π πππ radius π = 14 π. 1 π΄π·π΅ = πππππππ‘ππ ππ π πππππππππ = × 2ππ 2 1 22 π΄π·π΅ = × 2 ( ) (14) 2 7 π΄π·π΅ = 22 × 7 A triangular prism has two triangular bases at both ends and 3 rectangular surfaces on the other sides. Therefore, total surface area is the sum of the area of the 3 rectangles and 2 triangles. 78 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 π΄π·π΅ = 154 π (ii) 7. π΄πππ ππ π ππππππ = ππ 2 154 ππ2 = ππ 2 find the radius, r. 22 2 154 ππ2 = π 7 154 × 7 = 22π 2 154 × 7 22π 2 = 22 22 7 × 7 = π2 49 = π 2 πππ‘ππ ππππ = π΄πππ ππ π πππππππππ + ππππ ππ π‘πππππππ 1 2 1 πππ‘ππ ππππ = 308 + (BO)(BC) 2 1 πππ‘ππ ππππ = 308 + (14)(14) 2 πππ‘ππ ππππ = 308 + (7)(14) πππ‘ππ ππππ = 308 + 98 πππ‘ππ ππππ = 308 + bh πππ‘ππ ππππ = 406 π2 8(i) Divide the shape into 2 parts. π΄πππ = π × π π΄πππ 1 = 18 × 8 = 144 π2 π΄πππ 2 = 12 × 10 = 120 π2 πππ‘ππ ππππ = 144 π2 + 120 π2 πππ‘ππ ππππ = 264 π2 √49 = √π 2 7=π π = 7 ππ 8. Convert the cm to m. 47 47 ππ = π = 0.47 π 100 => 3.23 π + 47ππ + 5.1 π => 3.23 π + 0.47 π + 5.1 π Arrange the decimal points in a straight vertical line. A whole has a decimal point at the end. 3.23 π 0.47 π + 5.1 π_ 8.80 π_ 9. A closed cylinder has a circular lid, a circular base and a curved surface. (ii) πΆππ π‘ ππ ππππππ‘ = ππππ × πππ π‘ πππ π2 πΆππ π‘ ππ ππππππ‘ = 264 π2 × πΎ32.00/π2 πΆππ π‘ ππ ππππππ‘ = πΎ8 448 9 1 centimeter (cm) = 10 millimeters (mm) 58.74 ππ = 58.74 × 10 ππ = 587.4 ππ π΄πππ ππ πππ = ππ 2 π΄πππ ππ πππ π = ππ 2 π΄πππ ππ ππ’ππ£ππ π π’πππππ = 2ππβ Add the 3 surfaces to find the area of the closed cylinder. π΄πππ ππ ππππ ππ ππ¦ππππππ = ππ 2 + ππ 2 + 2ππβ 587.4 mm to the nearest millimeter is 587 mm because the number to the right of 7 is less than 5. (If it was 5 or greater, then the answer would be 588 mm after adding 1 to 7.) 79 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 1 × ππ 2 2 1 22 π΄πππ ππ π πππππππππ = × × (7)2 2 7 1 11 π΄πππ ππ π πππππππππ = × ×7×7 1 7 2 π΄πππ ππ π πππππππππ = 77 ππ π΄πππ ππ ππππ ππ ππ¦ππππππ = 2ππ 2 + 2ππβ π΄πππ ππ ππππ ππ ππ¦ππππππ = 2ππ(π + β) (substitute the values of r and h. 22 π΄πππ ππ ππππ ππ ππ¦ππππππ = 2 × × 7(7 + 5) 7 22 π΄πππ ππ ππππ ππ ππ¦ππππππ = 2 × × 1(12) 1 π΄πππ ππ ππππ ππ ππ¦ππππππ = 44 × 12 π΄πππ ππ ππππ ππ ππ¦ππππππ = 528 ππ2 π΄πππ ππ π πππππππππ = 13 π·πππππ‘ππ 14π₯ = = 7π₯ 2 2 (area of semi-circle = half of area of the circle) 1 π΄πππ ππ π πππππππππ = × ππ 2 2 1 22 π΄πππ ππ π πππππππππ = × × (7π₯)2 2 7 1 11 π΄πππ ππ π πππππππππ = × × 7π₯ × 7π₯ 1 7 11 π΄πππ ππ π πππππππππ = × π₯ × 7π₯ 1 π΄πππ ππ π πππππππππ = 77π₯ 2 π ππππ’π = π = 9 πͺππππππππππππ = ππ π π = πππππ’π = 14 ππ πΆππππ’ππππππππ = 2ππ 22 πΆππππ’ππππππππ = 2 × × 14 ππ 7 πΆππππ’ππππππππ = 2 × 22 × 2 ππ πΆππππ’ππππππππ = 88 ππ 10 Perimeter is the distance around a shape. πππππππ‘ππ = 2π₯ + 4π₯ + 5π₯ πππππππ‘ππ = 11π₯ ππ 14 AB is the diameter of the semi-circle. Radius is half of the diameter. π·πππππ‘ππ π ππππ’π = 2 π΄π΅ π ππππ’π = 2 11 1 πππ‘ππ = 10 ππ × 10 ππ × 10 ππ = 1 000 ππ3 1 ππ = 0.1 π 1 πππ‘ππ = 0.1 π × 0.1 π × 0.1 π = 0.001 π3 15 15 π3 = πππ‘πππ = 15 000 πππ‘πππ 0.001 (π΄π΅ = π·πΆ = 14 ππ) π ππππ’π = 12 14 ππ 2 π ππππ’π = 7 ππ 15 πβππππ ππππ = π πππ‘πππππ ππππ − ππππππππππ ππππ 1 πβππππ ππππ = π × π − × ππ 2 2 (area of semi-circle = half of area of the circle) 1 22 πβππππ ππππ = 14 × 10 − × × 72 2 7 πβππππ ππππ = 140 − 11 × 7 πβππππ ππππ = 140 − 77 πβππππ ππππ = 63 ππ2 Solution π ππππ’π = π = π·πππππ‘ππ 14 ππ = = 7ππ 2 2 16 Perimeter is the distance around a shape. πππππππ‘ππ = 1 + 7 + 11 + 7 + 1 + 8 + 13 + 8 π π΄πππ ππ ππππππ = ππ 2 (area of semi-circle = half of area of the circle) 80 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 22 × 21 × β 7 22 528 = 2 × × 21 × β 7 44 528 = ×3×β 1 πππππππ‘ππ = 56 π 528 = 2 × 528 = 132β 528 132β = 132 132 Note that the width of the lawn is 1 m. 4=β π = πππ 17 [2017.P1.Q20] The area of the base of a cylindrical block is 154cm2 and its height is 10cm as shown below. 19 A triangular prism has two triangular bases at both ends and 3 rectangular surfaces on the other sides. Therefore, total surface area is the sum of the area of the 3 rectangles and 2 triangles. π¨πππ ππ π πππππππππ = π × π π΄πππ ππ πππ π = 20 × 10 = 200 ππ2 π΄πππ ππ πππ π = 20 × 8 = 160 ππ2 π΄πππ ππ ππππ = 20 × 6 = 120 ππ2 π π¨πππ ππ π ππππππππ = × π × π π 1 π΄πππ ππ πππ = × 8 × 6 = 24 ππ2 2 1 π΄πππ ππ πππ = × 8 × 6 = 24 ππ2 2 πππ‘ππ ππππ = 200 + 160 + 120 + 24 + 24 ππ2 πππ‘ππ ππππ = 528 ππ2 Given that the mass of the block is 385g, find its density πππ π π·πππ ππ‘π¦ = ππππ’ππ ππππ’ππ ππ π π π¦ππππππ = π = ππ 2 β [ππ π = πππ π ππππ × βπππβπ‘] πππ π ππππ = 154ππ2 , β = βπππβπ‘ = 10ππ, 20 [2017.P2.Q7(c)] The diagram below is a cylinder of radius 5cm and height 7cm. 2 π = 154ππ × 10ππ, π = 1 540 ππ3 π·πππ ππ‘π¦ = πππ π 385π = = 0.25π/ππ3 ππππ’ππ 1 540 ππ3 18 π΄πππ ππ ππ¦ππππππ ππ’ππ£ππ π π’πππππ = 2ππβ 81 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Calculate its volume. ππππ’ππ ππ π π π¦ππππππ = π = ππ 2 β Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 πΉπΈπΊ + 120° = 180° πΉπΈπΊ = 180° − 120° πΉπΈπΊ = 60° [3] π = πππ π ππππ × βπππβπ‘ π = ππ 2 β π = 5ππ, β = 7ππ π= 3 180 − 50 2 130 π΄ππππ π΄πΆπ΅ = 2 π΄ππππ π΄πΆπ΅ = 65° 22 × 52 × 7 7 π΄ππππ π΄πΆπ΅ = π = 22 × 25 π = 550ππ3 π΄πΆπ΅ + π΄πΆπ· = 180° 65° + π΄πΆπ· = 180° π΄πΆπ· = 180° − 65° π΄πΆπ· = 115° 15 ANGLES (πΌπ ππ πππππ π‘πππππππ) (π π‘πππππβπ‘ ππππ) 4 Triangle PQR is an equilateral triangle because all 3 sides are equal. Therefore, all angles in it are equal and = 60°. π·ππ = πππ (πππ‘πππππ‘π ππππππ − ππππππππ πππππ ) πππ = 60° (πππ’ππππ‘ππππ π‘πππππππ πππ ) π·ππ = 60°. 1 Sum of angles around a point equals 360°. (One complete revolution.) π + 57 + π + 143 + 90 = 360 π + π + 57 + 143 + 90 = 360 π + π + 290 = 360 π + π = 360 − 290 π + π = 70 5 The sum of angles in a triangle equals 180° π₯ + (π₯ + 10) + (π₯ + 65) = 180 π₯ + π₯ + 10 + π₯ + 65 = 180 π₯ + π₯ + π₯ + 10 + 65 = 180 3π₯ + 75 = 180 3π₯ = 180 − 75 3π₯ = 105 3π₯ 105 = 3 3 π₯ = 35 . 6 An isosceles triangle has 2 equal sides and 2 equal angles. π΄π΅πΆ = π΅πΆπ΄ = π₯ π΅π΄πΆ + π΄π΅πΆ + π΅πΆπ΄ = 180° 3π₯ + π₯ + π₯ = 180° 5π₯ = 180° 5π₯ 180° = 5 5 π₯ = 36° 2 First find as many angles as possible (related to parallel lines and triangles) πΈπΉπΊ = π»πΈπ΅ (ππππππ πππππππ ππππππ ) πΈπΉπΊ = 50° πΈπΉπΊ + πΉπΈπΊ = πΈπΊπ· π π’π ππ 2 πππππ ππ‘π πππ‘. ππππππ = ππ₯π‘πππππ πππππ 50° + πΉπΈπΊ = 110° πΉπΈπΊ = 110° − 50° = 60° Method 2 π΅πΈπΊ + πΈπΊπ· = 180° (πππ. πππ‘πππππ ππππππ ) π΅πΈπΊ + 110° = 180° π΅πΈπΊ = 180° − 110° π΅πΈπΊ = 70° πΉπΈπΊ + π΅πΈπΊ + π»πΈπ΅ = 180° (π π‘ππππβπ‘ ππππ) πΉπΈπΊ + 70° + 50° = 180° 82 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 π₯ + 285° = 360° π₯ = 360° − 285° π₯ = 75° 10 π₯ = 23° + 78° (Exterior angle equals sum of two interior opposite angles) π₯ = 101° 7 π΄π΅πΆ = π΅π·πΈ π΄π΅πΆ = 80° π₯ + π¦ = 180° (straight line) 101° + π¦ = 180° π¦ = 180° − 101° π¦ = 79° πππ‘πππππ‘π ππππππ 11 Reflex angle = 360° − acute angle. π πππππ₯ πππππ = 360° − 45° π πππππ₯ πππππ = 315° 8(i) Triangle QPR is an isosceles triangle. This means that angle QPR = angle QRP angle QPR = (2π₯ + 50)° πππ + πππ + ππ π = 180° (π₯ + 30)° + (2π₯ + 50)° + (2π₯ + 50)° = 180° π₯° + 30° + 2π₯° + 50° + 2π₯° + 50° = 180° π₯° + 2π₯° + 2π₯° + 30° + 50° + 50° = 180° 5π₯° + 130° = 180° 5π₯° = 180° − 130° 5π₯° = 50° 5π₯° 50° = 5° 5° π₯ = 10 12 An isosceles triangle is a triangle that has two sides of equal length. The two angles formed by the equal sides are equal. (ππππππ ππ ππ ππ πππππ π‘πππππππ) πππ = ππ π πππ = 50° 13 Method 1 ππ π + ππ π = 180° (π π‘ππππβπ‘ ππππ = 180°) 50° + ππ π = 180° ππ π = 180° − 50° ππ π = 130° (ii) π ππ = ππ π ππ ππ πππππ π‘πππππππ π ππ = (2π₯ + 50)° we found that π₯ = 10 π ππ = (2 × 10 + 50)° π ππ = (20 + 50)° π ππ = 70° Method 2 ππ π + π ππ + πππ = 180° (angles in a triangle) (π ππ = πππ = 25° ππ ππ πππππ π‘πππππππ) ππ π + π ππ + πππ = 180° ππ π + 25° + 25° = 180° ππ π + 50° = 180° ππ π = 180° − 50° ππ π = 130° 9 Angles around a point will always add up to 360 degrees. π₯ + 75° + 120° + 90° = 360° 14(i) π·πΆπΈ = π΅π·πΆ 83 (πππ‘πππππ‘π ππππππ ) FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 Note: Supplementary angles add up to 180°. π·πΆπΈ = 45° (ii) π΅πΆπ· + π΅π·πΆ = π΄π΅π· (Exterior angle equals sum of two interior opposite angles) π΅πΆπ· + π΅π·πΆ = π΄π΅π· π΅πΆπ· + 45° = 75° π΅πΆπ· = 75° − 45° π΅πΆπ· = 30° 18 Triangle ABC is an isosceles triangle. <ABC = <ACB 15 πΆπ΅π· + π΅πΆπ· = πΆπ·πΈ (Exterior angle equals sum of two interior opposite angles) πΆπ΅π· + 70° = 150° πΆπ΅π· = 150° − 70° πΆπ΅π· = 80° 5π₯ + 30 = 180 <DCE = <ACB (opposite angles <ABC = <ACB = <DCE = 2π₯ + 15 πΆπ΄π΅ + π΄π΅πΆ + π΄πΆπ΅ = 180° π₯ + 2π₯ + 15 + 2π₯ + 15 = 180 π₯ + 2π₯ + 2π₯ + 15 + 15 = 180 5π₯ = 180 − 30 5π₯ 150 = 5 5 π₯ = 30 16 GEOMETRICAL CONSTRUCTION 1 π + π = π (Exterior angle equals sum of two interior opposite angles) 16 Angle APQ= 130° and angle PQC are adjacent angles (opposite interior angles). This means that they supplementary angles (add up to 180°). πππΆ + π΄ππ = 180° πππΆ + 130° = 180° πππΆ = 180° − 130° πππΆ = 50° 17 Complementary angles add up to 90°. π₯° + (3π₯ − 2)° = 90° π₯° + 3π₯° − 2° = 90° 4π₯° = 90° + 2° 4π₯° = 92° 2 (i) Construct triangle LMN in which LM = 7cm, MN = 5cm and LN = 6cm. Step 1 – use a ruler to draw one side. 4π₯° 92° = 4 4 π = ππ 84 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 (ii) Bisect angle LNM and angle LMN and label the point of intersection of the angle bisectors as O. Step 2 – use a compass with radius of 5 cm, fix the pin on point M and draw an arc as shown below. Step 3 – use a compass with radius of 6 cm, fix the pin on point L and draw an arc as shown below. Step 4 – draw straights from M and from L to the point where the two arcs cross each other as shown below. (iii) Draw a perpendicular from O to the side LM. Label the point where the perpendicular meets LM as P. 85 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, (ii) (iv) With O as the centre, draw a circle which touches all the three sides of the triangle LMN. (iii) 3 (i) (iv) 86 Mathematics 8 - 9 0968-747007, 0955-747000 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 4(i) (iii) (ii) Use a protractor to measure angle ABC. ABC = 42°. 87 Mathematics 8 - 9 0968-747007, 0955-747000 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 (iv) 5(i) Step 1 – use a ruler to draw one side. Step 4 – draw straights from A and from B to the point where the two arcs cross each other as shown below. Step 2 – use a compass with radius of 8 cm, fix the pin on point A and draw an arc as shown below. (ii) To bisect AB, Place the compass pin at point A and draw an arc on both sides of the line AB as shown below. Then place the compass pin at point B and draw an arc on both sides of the line as shown below. Join the two points where the arcs cross each other. This line is the bisector of line AB. Step 3 – use a compass with radius of 9 cm, fix the pin on point B and draw an arc as shown below. 88 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 The centre of the circle that passes through all three edges of a triangle is the point where bisectors of any two sides of the triangle meet. Place the compass pin on the point where the bisectors meet and increase the radius until it can reach A, B or C, then draw the circle as shown below. To bisect BC, Place the compass pin at point B and draw an arc on both sides of the line BC as shown below. Then place the compass pin at point C and draw an arc on both sides of the line BC as shown below. Join the two points where the arcs cross each other. This line is the bisector of line BC. 6 (i) (ii) (iii) (iv) [2017.P2.Q4(c)] Follow method in 4(i) Follow method in 4(ii). Follow method in 5(ii) Follow method in 5(iii) 17 STATISTICS 1 To find the Median, place the numbers you are given in value order and find the middle number. If there are two middle numbers, you average them (find the average). 1, 0, 2, 2, 0, 4, 2, 3, 1, 2. re-arrange the numbers in increasing order (iii) 89 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 0, 0, 1, 1, 2, 2, 2, 2, 3, 4. There are 10 numbers, the middle numbers are 2 and 2. The average of 2 and 2 is 2. Therefore, the median is 2. Mathematics 8 - 9 0968-747007, 0955-747000 Find the angle for Kalembula πΎ200 → 200 × 360° = 120° 600 Find the angle for Chibwabwa 2 Learners that like blue correspond to 80° on the pie chart. Total number of learners corresponds to 360°. πΎ150 → 150 × 360° = 90° 600 Find the angle for Tomatoes 40 → 80° π₯ → 360° cross multiply π₯ × 80 = 40 × 360 πΎ250 → 250 × 360° = 150° 600 80π₯ = 14 400 Use a protractor to measure and draw the angles as divide both sides by 80 shown below. 80π₯ 14 400 = 80 80 π₯ = 180 ππππππππ 3 [2016.P2.Q4c] A marketer made K200.00 profit from Kalembula, K150.00 profit from Chibwabwa and K250.00 profit from tomatoes. Illustrate this information on the pie chart below. 4 (i) How many games did the team play? 6 + 8 + 3 + 2 + 1 = 20 πππππ (ii) Complete the frequency table below. Number of goals Number of games 1 6 2 8 3 3 The sum of all the angles in a pie chart is 360°. (Sum of angles around a point is 360°.) 4 πΎ200 + πΎ150 + πΎ250 → 360° Mean means average. ππ’π ππ πππ ππ‘πππ ππππ (ππ£πππππ) = ππ’ππππ ππ ππ‘πππ πΎ600 → 360° 90 4 2 5 1 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM ππππ = 17 + 43 + 15 + 22 + 18 5 ππππ = 115 = 23 5 Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 10 + 14 = 12 2 15 + 19 π‘βπ πππ − πππππ‘ ππ 15 − 19 = = 17 2 π‘βπ πππ − πππππ‘ ππ 10 − 10 = ππππ ππππ = = 5 ππ’π ππ πππππ’ππ‘π πππ − πππππ‘π & πππππ’ππππππ π π’π ππ πππ πππππ’ππππππ πππ§π 7 = 2 ππ’ππππ 2 × 7 + 7 × 8 + 12 × 3 + 17 × 2 7+8+3+2 14 + 56 + 36 + 34 ππππ ππππ = 20 140 ππππ ππππ = 20 πππ‘ππ ππ’ππππ = 14 + 12 + 2 = 28 ππ’ππππ ππππ ππππ = 7 πππππ Find the number of pupils who wear size 5, size 6 and ππππ ππππ = size 7. πππ§π 5 = 14 ππ’ππππ πππ§π 6 = 12 ππ’ππππ 7 First find the total for each farmer as shown below. 2010 2011 2012 2013 2014 TOTAL Mr Hapopwe 10 25 40 35 30 140 Mr Milisi 15 25 30 35 30 135 πβπ ππππππππππ = 140 − 135 = 5 ππππ . 8 54 + 6π₯ = 60 7 54 + 6π₯ = 60 × 7 54 + 6π₯ = 420 6π₯ = 420 − 54 6π₯ = 366 6π₯ 366 = 6 6 π₯ = 61 ππ Average mass of 6 girls = 61 ππ 6 (i) Modal class or mode is the range with the highest frequency. In this case it is 5 − 9. (ii) The mean is the average. ππππ ππππ = = ππ’π ππ πππππ’ππ‘π πππ − πππππ‘π & πππππ’ππππππ π π’π ππ πππ πππππ’ππππππ 0+4 = 2 2 5+9 π‘βπ πππ − πππππ‘ ππ 5 − 9 = = 7 2 π‘βπ πππ − πππππ‘ ππ 0 − 4 = 9(i) The sum of all the angles in a pie chart is 360°. (Sum of angles around a point is 360°.) 91 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, πΉπππ + πΊππππππππ + πππππ ππππ‘ = 360° π₯ + 90° + 60° = 360° π₯ + 150° = 360° π₯ = 360° − 150° π₯ = 210° Mathematics 8 - 9 0968-747007, 0955-747000 Draw horizontal lines from the top of the bar to the yaxis and get the value in tonnes. 2006 – 2 tonnes 2007 – 4 tonnes 2008 – 2 tonnes 2009 – 6 tonnes 2010 – 4 tonnes (ii) Total amount K1 200.00 corresponds 360° Amount on transport, π, corresponds to 60°. πΎ1 200 → 360° π‘ → 60° cross multiply π‘ × 360° = πΎ1 200 × 60° 360π‘ = πΎ1 200 × 60 360π‘ πΎ72 000 = 360 360 π‘ = πΎ200 Amount on transport = πΎ200 Now add the tonnes together. 2 + 4 + 2 + 6 + 4 = 18 π‘πππππ (iii) πΊππππππππ ππππ’ππ‘ × 100% πππ‘ππ ππππ’ππ‘ 300 = × 100% 1200 300 = × 1% 12 100 = × 1% 4 = 25% πΊππππππππ πππππππ‘πππ = πΊππππππππ πππππππ‘πππ πΊππππππππ πππππππ‘πππ πΊππππππππ πππππππ‘πππ πΊππππππππ πππππππ‘πππ 12 To find the Median, place the numbers you are given in value order and find the middle number. If there are two middle numbers, you average them (find the average). 24, 18, 17, 16, 20, 30, 16 re-arrange the numbers in increasing order 16, 16, 17, 18, 20, 24, 30 There are 7 numbers, the middle number (4th number) is 18. Therefore, the median is 18. 10 Let cost price be π₯ πΆππ π‘ πππππ + ππππππ‘ = π ππππππ πππππ π₯ + 20% ππ π₯ = πΎ60 20 π₯+ × π₯ = πΎ60 100 20π₯ π₯+ = πΎ60 100 100π₯ + 20π₯ = πΎ60 100 120π₯ = πΎ60 100 120π₯ = πΎ6 000 120π₯ πΎ6 000 = 120 120 π₯ = πΎ50 πΆππ π‘ πππππ = πΎ50.00 13(i) 240 × 360° = 144° 600 160 ππ’π ππ π£πππ€πππ = × 360° = 96° 600 150 πππ£ππ π£πππ€πππ = × 360° = 90° 600 50 πππ€π π£πππ€πππ = × 360° = 30° 600 πππππ‘π π£πππ€πππ = 11 92 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 0, 0, 1, 2, 2, 3, 4, 4, 4, 5. ππππππ = 2+3 = 2.5 2 Note: mean: regular meaning of "average" median: middle value mode: most often (most frequent value) (ii) Use a protractor to draw the angles. 15 The score of 2 is the modal score since it appears most frequently. Mode is the item with the highest frequency (appears most frequently). 16(i) ππππβπ’π βπππ‘ππππ πππ‘ππ βπππ‘ππππ 2 πΉππππ‘πππ ππ ππππβπ’π = 4+2+1+3 2 πΉππππ‘πππ ππ ππππβπ’π = 10 1 πΉππππ‘πππ ππ ππππβπ’π = 5 πΉππππ‘πππ ππ ππππβπ’π = (ii) 14 Median is the middle number in a given sequence of numbers, taken as the average of the two middle numbers when the sequence has an even number of numbers. Since the median is 2.5 (the average of 2 and 3), it means that x = 1, to make the sum of the frequencies to be 10. The frequencies to the left of x are 2 + 1 + 2 = 5. The frequencies to the right of x are 3 + 1 = 4. To make the sum of all the frequencies to be 10, x must be 1. Meaning there is one score of 3 goals. When arranged from smallest to largest, the scores are: 17 π΄π£πππππ πππ π = ππ’π ππ πππ πππ π ππ ππ’ππππ ππ ππππππ π΄π£πππππ πππ π = 93 3.1ππ + 2.6ππ + 3.3ππ + 2.8ππ ππ’ππππ ππ ππππππ FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 11.8 ππ 4 11.8 ππ π΄π£πππππ πππ π = 4 Mathematics 8 - 9 0968-747007, 0955-747000 Learners scored more than five marks= 7 + 10 + 2 = 19 learners π΄π£πππππ πππ π = π΄π£πππππ πππ π = 2.95 ππ 22 [2017.P2.Q6(c)] The sum of all the angles in a pie chart is 360°. (Sum π΄π£πππππ πππ π = 3 ππ (to the nearest kg) of angles around a point is 360°.) 13 + 5 + 8 + 4 → 360° 30 → 360° 18 ππ’π ππ πππ βπππβπ‘π π΄π£πππππ βπππβπ‘ = ππ’ππππ ππ ππππππ 1.25 + π₯ 1.4 = 4 π₯ ππ π‘ππ‘ππ βπππβπ‘ ππ ππ‘βππ 3 πβππππππ Cross multiply 1.4 × 4 = 1.25 + π₯ Find the angle for Green 13 → 13 × 360° = 156° 30 Find the angle for Blue. 5.6 = 1.25π₯ 5→ 5.6 1.25π₯ = 1.25 1.25 4.48 = π₯ 5 × 360° = 60° 30 Find the angle for Red π₯ = 4.48 π 8→ 8 × 360° = 96° 30 19 Letter A is the modal letter since it appears most frequently. Mode is the item with the highest frequency (appears most frequently) Find the angle for Yellow 20 Note: mean: regular meaning of "average" median: middle value mode: most often (most frequent value) Use a protractor to measure and draw the angles as 8→ shown below. Median is the middle number in a given sequence of numbers, taken as the average of the two middle numbers when the sequence has an even number of numbers. The numbers must first be arranged in ascending order. 2, 3, 3, 5, 6, 7, 10. 5 is in the middle. ππππππ = 5 21 4 × 360° = 48° 30 7 learners scored 6 marks 10 learners scored 7 marks 2 learners scored 8 marks 94 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 23 [2017.P2.Q8(c)] The table below shows how Mwanga spends his time in a day. Activity No. of hours Relaxi ng 6 Lesso ns 7 Studyi ng 3 Sleepi ng 8 Use this information to complete the bar chart below. [3] 18 NUMBER BASES 1 First convert 4.25 to a fraction 425 17 4.25 = = 100 4 Then convert the numerator and denominator to base 2. Change the numerator 17 to base 2. 95 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 17 ÷ 2 = 8 8÷2 =4 4÷2 =2 2÷2 =1 1÷2 =0 Call 0977-747000, πππππππππ π πππππππππ π πππππππππ π πππππππππ π πππππππππ π Mathematics 8 - 9 0968-747007, 0955-747000 3 × 3 = 9 → (9 + 1) ÷ 5 = 2 πππππππππ 0 So we write the remainder 0 and ‘carry’ 2 to the left. The 1 added to 9 above is the ‘carried 1’ in the previous operation. 432 × 23 01 . You keep dividing by 2 until you get 0 (zero). Write the remainders from bottom up. That will give us 10001π‘π€π Therefore, 17 = 10001π‘π€π 3 × 4 = 12 → (12 + 2) ÷ 5 = 2 πππππππππ 4 So we write the remainder 4 and ‘carry’ 2 to the left. The 2 added to 12 above is the ‘carried 2’ in the previous operation. 432 × 23 401 . Now change the denominator 4 to base 2 4÷2 =2 πππππππππ π 2÷2 =1 πππππππππ π 1÷2 =0 πππππππππ π You keep dividing by 2 until you get 0 (zero). Write the remainders from bottom up. That will give us 100π‘π€π Therefore, 4 = 100π‘π€π Now we have 425 17 10001π‘π€π 4.25 = = = = 100.01π‘π€π 100 4 100π‘π€π Since there are no more numbers to be multiplied by 3, we write down the carried ‘2’ in the fourth column. 432 × 23 2401 . Note! Dividing by 100 in whatever base results in the point moving two steps to the left. Now multiply 432 by 2 Before we start multiplying we write down 0 under the first column since 2 is in the ‘tens’ column as shown below. 432 × 23 2401 0 . 2 Method 1 Multiply in base 5. First, multiply 432 by 23. 432 × 23 . 2 × 2 = 4 → 4 ÷ 5 = 0 πππππππππ 4 4 divided by 5 (since this is base 5) = 0 remainder 4. So we write the remainder 4 and ‘carry’ nothing to the left. 432 × 23 2401 40 . 3 × 2 = 6 → 6 ÷ 5 = 1 πππππππππ 1 6 divided by 5 (since this is base 5) = 1 remainder 1. So we write the remainder 1 and ‘carry’ 1 to the left. 432 × 23 1 . 96 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 2 × 3 = 6 → 6 ÷ 5 = 1 πππππππππ 1 So we write the remainder 1 as shown below and ‘carry’ 1 to the left column. 432 × 23 2401 140 . Mathematics 8 - 9 0968-747007, 0955-747000 × 14 432 × 23 2401 14140 . 41 . Looking at the third column from right: 4 + 1 = 5 → 5 ÷ 5 = 1 πππππππππ 0 Write down the remainder 0, and ‘carry’ the 1 to the column on the left. 432 × 23 2401 14140 . 041 . 2 × 4 = 8 → (8 + 1) ÷ 5 = 1 πππππππππ 4 So we write the remainder 4 and ‘carry’ 1 to the left. The 1 added to 8 above is the ‘carried 1’ in the previous operation. 432 × 23 2401 4140 . Looking at the fourth column from right: 2 + 4 = 6 → (6 + 1) ÷ 5 = 1 πππππππππ 2 The 1 added to 6 above is the ‘carried 1’ in the previous operation. Write down the remainder 2, and ‘carry’ the 1 to the column on the left. 432 × 23 2401 14140 . 2041 . Since there are no more numbers to be multiplied by 2, we write down the carried ‘1’ in the fifth column. 432 × 23 2401 14140 . ___________ Next, we do the addition. 432 × 23 2401 14140 . ___________ Looking at the fifth column from right: 0 + 1 = 1 → (1 + 1) ÷ 5 = 0 πππππππππ 2 The 1 added to 1 above is the ‘carried 1’ in the previous operation. Write down the remainder 2. There is nothing to ‘carry’ over to the column on the left. End of operation! Looking at the first column from right: 1 + 0 = 1 → 1 ÷ 5 = 0 πππππππππ 1 Write down the remainder 3 and ‘carry’ nothing. 432 × 23 2401 14140 . 1 . 432 × 23 2401 14140 . 22041 . 432πππ£π × 23πππ£π = πππππππππ Looking at the second column from right: 0 + 4 = 4 → 4 ÷ 5 = 0 πππππππππ 4 Write down the remainder 4 and ‘carry’ nothing. 32 Method 2 97 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 First convert both numbers from base five to base ten, then multiply the two numbers in base ten and convert the answer to base 5. 3 Change to base 10. When converting from base 5 to base 10: Step 1 Multiply the first digit (from the right) by 50 = 1 Step 2 Multiply the second digit (from the right) by 51 = 5 Step 3 Multiply the third digit (from the right) by 52 = 25 Step 4 Multiply the fourth digit (from the right) by 53 = 125 Keep increasing the power of 5 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). Note! Dividing by 100 in whatever base results in the point moving two steps to the left. 432πππ£π = 4 × 52 + 3 × 51 + π × 50 = 4 × 25 + 3 × 5 + π × 1 = 100 + 15 + π = 117 1100π‘π€π = 1 × 23 + 1 × 22 + 0 × 21 + 0 × 20 1100π‘π€π = 1 × 8 + 1 × 4 + 0 × 2 + 0 × 1 1100π‘π€π = 8 + 4 + 0 + 0 = ππ 1 1100π‘π€π ÷ 100π‘π€π = Or use long division Or convert both to base ten, divide, then change the answer back to base two. 1100π‘π€π ÷ 100π‘π€π = 12 ÷ 4 = 3 = 11π‘π€π 100π‘π€π = 1 × 22 + 0 × 21 + 0 × 20 100π‘π€π = 1 × 4 + 0 × 2 + 0 × 1 100π‘π€π = 4 + 0 + 0 = π 0 23πππ£π = 2 × 5 + π × 5 = 2×5+π×1 = 10 + π = 13 12 ÷ 4 = π 432πππ£π × 23πππ£π = 117 × 13 = 1521 Change 3 to base 2 3 ÷ 2 = 1 πππππππππ π 1 ÷ 2 = 0 πππππππππ π Write the remainders from bottom up. That will give us 11π‘π€π Change 1521 from base 10 to base five. 1521 ÷ 5 = 304 304 ÷ 5 = 60 60 ÷ 5 = 12 12 ÷ 5 = 2 2÷5= 0 1100π‘π€π = 11π‘π€π 100π‘π€π πππππππππ π πππππππππ π πππππππππ π πππππππππ π πππππππππ π 3 = 11π‘π€π Write the remainders from bottom up. That will give us 22041πππ£π Therefore, 432πππ£π × 23πππ£π = 117 × 13 = 1521 = πππππππππ 4 First change the bicimal to fraction 11011π‘π€π 11.011π‘π€π = 1000π‘π€π 98 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Now change the numerator and denominator to base 10. When converting from base 2 to base 10: Step 1 Multiply the first digit (from the right) by 20 = 1 Step 2 Multiply the second digit (from the right) by 21 = 2 Step 3 Multiply the third digit (from the right) by 22 = 4 Step 4 Multiply the fourth digit (from the right) by 23 = 8 Keep increasing the power of 2 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). Or convert both to base ten, divide, then change the answer back to base two. 1111π‘π€π = 1 × 23 + 1 × 22 + 1 × 21 + 1 × 20 1111π‘π€π = 1 × 8 + 1 × 4 + 1 × 2 + 1 × 1 1111π‘π€π = 8 + 4 + 2 + 1 = ππ 11π‘π€π = 1 × 21 + 1 × 20 11π‘π€π = 1 × 2 + 1 × 1 11π‘π€π = 2 + 1 = π 11011π‘π€π = 1 × 24 + 1 × 23 + 0 × 22 + 1 × 21 + 1 × 20 11011π‘π€π = 1 × 16 + 1 × 8 + 0 × 4 + 1 × 2 + 1 ×1 11011π‘π€π = 16 + 8 + 0 + 2 + 1 11011π‘π€π = ππ 1111π‘π€π ÷ 11π‘π€π = 15 ÷ 3 = 5 Change 5 to base 2 5 ÷ 2 = 2 πππππππππ π 2 ÷ 2 = 1 πππππππππ π 1 ÷ 2 = 0 πππππππππ π Write the remainders from bottom up. That will give us 101π‘π€π 1000π‘π€π = 1 × 23 + 0 × 22 + 0 × 21 + 0 × 20 1000π‘π€π = 1 × 8 + 0 × 4 + 0 × 2 + 0 × 1 1000π‘π€π = 8 + 0 + 0 + 0 1000π‘π€π = 8 Therefore, 11.011π‘π€π = Mathematics 8 - 9 0968-747007, 0955-747000 11011π‘π€π 27 = = 3.375 1000π‘π€π 8 5 = 101π‘π€π 1111π‘π€π ÷ 11π‘π€π = 15 ÷ 3 = 5 = 101π‘π€π 5 7 [2015.P2.7b] ππ’ππ‘ππππ¦ 144πππ£π ππ¦ 13πππ£π , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π πππ£π. 1111π‘π€π 1111π‘π€π ÷ 11π‘π€π = = 101π‘π€π 11π‘π€π Or use long division Method 1 Multiply in base 5. First, multiply 144 by 3. 144 × 13 99 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 1042 0 . . 3 × 4 = 12 → 12 ÷ 5 = 2 πππππππππ 2 12 divided by 5 (since this is base 5) = 2 remainder 2. So we write the remainder 2 and ‘carry’ 2 to the left. 144 × 13 2 . 1 × 4 = 4 → 4 ÷ 5 = 0 πππππππππ 4 4 divided by 5 (since this is base 5) = 0 remainder 4. So we write the remainder 4 and ‘carry’ nothing to the left. 144 × 13 1042 40 . 3 × 4 = 12 → (12 + 2) ÷ 5 = 2 πππππππππ 4 14 divided by 5 (since this is base 5) = 2 remainder 4. So we write the remainder 4 and ‘carry’ 2 to the left. The 2 added to 12 above is the ‘carried 2’ in the previous operation. 144 × 13 42 . 1 × 4 = 4 → 4 ÷ 5 = 0 πππππππππ 4 4 divided by 5 (since this is base 5) = 0 remainder 4. So we write the remainder 4 and ‘carry’ nothing to the left. Note that there noting carried over from the previous operation. 144 × 13 1042 440 . 3 × 1 = 3 → (3 + 2) ÷ 5 = 1 πππππππππ 0 So we write the remainder 0 and ‘carry’ 1 to the left. The 2 added to 3 above is the ‘carried 2’ in the previous operation. 144 × 13 042 . 1 × 1 = 1 → 1 ÷ 5 = 0 πππππππππ 1 So we write the remainder 1 and ‘carry’ nothing to the left. 144 × 13 1042 1440 . Next, we do the addition. 144 × 13 1042 1440 . ___________ Since there are no more numbers to be multiplied by 3, we write down the carried ‘1’ in the fourth column. 144 × 13 1042 . Looking at the first column from right: 2 + 0 = 2 → 2 ÷ 5 = 0 πππππππππ 2 Write down the remainder 2 and ‘carry’ nothing. 144 × 13 1042 1440 . 2 . Now multiply 144 by 1 Before we start multiplying we write down 0 under the first column since 1 is in the ‘tens’ column as shown below. 144 × 13 100 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 Multiply the second digit (from the right) by 51 = 5 Step 3 Multiply the third digit (from the right) by 52 = 25 Step 4 Multiply the fourth digit (from the right) by 53 = 125 Keep increasing the power of 5 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). Looking at the second column from right: 4 + 4 = 8 → 8 ÷ 5 = 1 πππππππππ 3 Write down the remainder 3 and ‘carry’ 1 to the left.. 144 × 13 1042 1440 . 32 . Looking at the third column from right: 0 + 4 = 4 → (4 + 1) ÷ 5 = 1 πππππππππ 0 Write down the remainder 0, and ‘carry’ the 1 to the column on the left. The 1 added to 4 above is the one carried from the previous operation. 144 × 13 1042 1440 . 032 . 144πππ£π = 1 × 52 + 4 × 51 + π × 50 = 1 × 25 + 4 × 5 + π × 1 = 25 + 20 + π = 49 13πππ£π = 1 × 51 + π × 50 = 1×5+π×1 =5+π =8 144πππ£π × 13πππ£π = 49 × 8 = 392 Looking at the fourth column from right: 1 + 1 = 2 → (2 + 1) ÷ 5 = 0 πππππππππ 3 The 1 added to 2 above is the ‘carried 1’ in the previous operation. Write down the remainder 3, and ‘carry’ the nothing. 144 × 13 1042 1440 . 3032 . Change 392 from base 10 to base five. Keep dividing by 5 until the answer is 0. 392 ÷ 5 = 78 πππππππππ π 78 ÷ 5 = 15 πππππππππ π 15 ÷ 5 = 3 πππππππππ π 3÷5= 0 πππππππππ π Write the remainders from bottom up. That will give us 3032πππ£π Therefore, 144πππ£π × 13πππ£π = 49 × 8 = 392 = 3032πππ£π End of operation! 144πππ£π × 13πππ£π = 3032ππππ Method 2 First convert both numbers from base five to base ten, then multiply the two numbers in base ten and convert the answer to base 5. 8 31πππ£π × 11πππ£π Change to base 10. When converting from base 5 to base 10: Step 1 Multiply the first digit (from the right) by 50 = 1 Step 2 Method 1 Multiply in base 5. First, multiply 31 by 1. 31 101 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM × Call 0977-747000, 11 Mathematics 8 - 9 0968-747007, 0955-747000 Next, we do the addition. . Looking at the first column: 1 + 1 = 2 → 2 ÷ 5 = 0 πππππππππ 2 Write down the remainder 2. 31 × 11 31 + 310 . 2__ 1 × 1 = 1 → 1 ÷ 5 = 0 πππππππππ 1 1 divided by 5 (since this is base 5) = 0 remainder 1. So we write the remainder 1 and ‘carry’ nothing (or 0) to the left. 31 × 11 1 . Looking at the second column: 3 + 1 = 4 → 4 ÷ 5 = 0 πππππππππ 4 Write down the remainder 4. 31 × 11 31 + 310 . 42__ 1 × 3 = 3 → 3 ÷ 5 = 0 πππππππππ 3 So we write the remainder 3 and ‘carry’ nothing to the left. 31 × 11 31 . Looking at the third column: 0 + 3 = 3 → 3 ÷ 5 = 0 πππππππππ 3 Write down the remainder 3. 31 × 11 31 + 310 . 341__ Now multiply 31 by 1 Before we start multiplying we write down 0 under the first column since 1 is in the second column as shown above. 31 × 11 31 0. 31πππ£π × 11πππ£π = 342πππ£π 1 × 1 = 1 → 1 ÷ 5 = 0 πππππππππ 1 So we write the remainder 1 and ‘carry’ 0 (nothing) to the left as shown above. 31 × 11 31 10 . Method 2 First convert both numbers from base five to base ten, then multiply the two numbers in base ten and convert the answer to base 5. Change to base 10. When converting from base 5 to base 10: Step 1 Multiply the first digit (from the right) by 50 = 1 Step 2 Multiply the second digit (from the right) by 51 = 5 Step 3 Multiply the third digit (from the right) by 52 = 25 Step 4 Multiply the fourth digit (from the right) by 53 = 125 1 × 3 = 3 → 3 ÷ 5 = 0 πππππππππ 3 So we write the remainder 3 as shown above 31 × 11 31 310 . . 102 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 Keep increasing the power of 5 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). Multiply the fourth digit (from the right) by 83 = 512 Keep increasing the power of 8 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). 31πππ£π = π × 51 + π × 50 = 3×5+1×1 = 15 + π = 16 531πππβπ‘ + 77πππβπ‘ = ______ 531πππβπ‘ 531πππβπ‘ 531πππβπ‘ 531πππβπ‘ 11πππ£π = π × 51 + π × 50 = 1×5+π×1 =5+π =6 = 5 × 82 + 3 × 81 + 1 × 80 = 5 × 64 + 3 × 8 + 1 × 1 = 320 + 24 + 1 = 345 = 7 × 81 + 7 × 80 =7×8+7×1 = 56 + 7 = 63 31πππ£π × 11πππ£π = 16 × 6 = 96 77πππβπ‘ 77πππβπ‘ 77πππβπ‘ 77πππβπ‘ 9 Change 17 from base 10 to base five. 531πππβπ‘ + 77πππβπ‘ = 345 + 63 = 408 17 ÷ 5 = 3 3÷5= 0 Now change 408 from base 10 to 8. πππππππππ π πππππππππ π Keep dividing by 5 until the answer is 0. Write the remainders from bottom up. That will give us 32πππ£π Therefore, 17π‘ππ = 32πππ£π 408 ÷ 8 = 51 πππππππππ π 51 ÷ 8 = 6 πππππππππ π 6÷8= 0 πππππππππ π Write the remainders from bottom up. That will give us 630πππβπ‘ Therefore, 531πππβπ‘ + 77πππβπ‘ = 345 + 63 = 408 = 630πππβπ‘ 10 Method 1 First convert both numbers from base eight to base 10, then add the two numbers. Finally convert the number from base 10 to base 8 . When converting from base 8 to base 10: Step 1 Multiply the first digit (from the right) by 80 = 1 Step 2 Multiply the second digit (from the right) by 81 = 8 Step 3 Multiply the third digit (from the right) by 82 = 64 Step 4 Method 2 Add in base 8. When adding in base 8, you have to divide the answer by 8 and write down the remainder as explained below. 531 + 77 . Add the first column from the right. 1 + 7 = 8 → 8 ÷ 8 = 1 πππππππππ 0 Write down the remainder 0 and ‘carry’ 1 to the next column to the left.. 531 + 77 103 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 1011π‘π€π = 8 + 0 + 2 + 1 1011π‘π€π = ππ 0 . 1 (‘carried’ 1’s) Add the second column from the right and add the ‘carried’ 1.. 3 + 7 = 10 10 + π‘βπ πππππππ 1 = 11 → 11 ÷ 8 = 1 πππππππππ 3 Write down the remainder 3 and ‘carry’ 1 to the next column to the left.. 531 + 77 30 . 11 (‘carried’ 1’s) 12 Method 1 First convert both numbers from base two to base 10, then multiply the two numbers (which are already in base 10). When converting from base 2 to base 10: Step 1 Multiply the first digit (from the right) by 20 = 1 Step 2 Multiply the second digit (from the right) by 21 = 2 Step 3 Multiply the third digit (from the right) by 22 = 4 Step 4 Multiply the fourth digit (from the right) by 23 = 8 Keep increasing the power of 2 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). Add the third column from the right. 5+0 =5 5 + π‘βπ πππππππ 1 = 6 → 6 ÷ 8 = 0 πππππππππ 6 Write down the remainder 6. There is nothing to carry to the next column. 531 + 77 630 . 11 (‘carried’ 1’s) Therefore, 531πππβπ‘ + 77πππβπ‘ = 630πππβπ‘ 1101π‘π€π = 1 × 23 + 1 × 22 + 0 × 21 + 1 × 20 1101π‘π€π = 1 × 8 + 1 × 4 + 0 × 2 + 1 × 1 1101 two = 8 + 4 + 0 + 1 ππππ ππ°π¨ = ππ 11 When converting from base 2 to base 10: Step 1 Multiply the first digit (from the right) by 20 = 1 Step 2 Multiply the second digit (from the right) by 21 = 2 Step 3 Multiply the third digit (from the right) by 22 = 4 Step 4 Multiply the fourth digit (from the right) by 23 = 8 Keep increasing the power of 2 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). 1111π‘π€π = 1 × 23 + 1 × 22 + 1 × 21 + 1 × 20 1111 two = 1 × 8 + 1 × 4 + 1 × 2 + 1 × 1 1111 two = 8 + 4 + 2 + 1 ππππ ππ°π¨ = ππ Therefore, 1101π‘π€π π‘π 1111π‘π€π = 13 + 15 = 28 Method 2 First add in base 2, then convert to base 10. 1101 + 1111 . Add the first column from the right. 1 + 1 = 2 → 2 ÷ 2 = 1 πππππππππ 0 1011π‘π€π = 1 × 23 × +0 × 22 + 1 × 21 + 1 × 20 1011π‘π€π = 1 × 8 + 0 × 4 + 1 × 2 + 1 × 1 104 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 Write down the remainder 0 and ‘carry’ 1 to the next column to the left.. 1101 + 1111 0 . 1 Multiply in base 5. First, multiply 32 by 4. 32 × 14 Add the second column from the right. 0+1 =1 1 + π‘βπ πππππππ 1 = 2 → 2 ÷ 2 = 1 πππππππππ 0 Write down the remainder 0 and ‘carry’ 1 to the next column to the left.. 1101 + 1111 00 . 11 (carried 1’s) 4 × 2 = 8 → 8 ÷ 5 = 1 πππππππππ 3 8 divided by 5 (since this is base 5) = 1 remainder 3. So we write the remainder 3 and ‘carry’ 1 to the left. 32 × 14 3 . . 4 × 3 = 12 → (12 + 1) ÷ 5 = 2 πππππππππ 3 So we write the remainder 3 and ‘carry’ 2 to the left. The 1 added to 12 above is the ‘carried 1’ in the previous operation. 32 × 14 33 . Add the third column from the right. 1+1 =2 2 + π‘βπ πππππππ 1 = 3 → 3 ÷ 2 = 1 πππππππππ 1 Write down the remainder 1 and ‘carry’ 1 to the next column to the left.. 1101 + 1111 100 . 111 (carried 1’s) Since there are no more numbers to be multiplied by 4, so we write down the carried ‘2’ in the third column. 32 × 14 233 . Add the fourth column from the right. 1+1 =2 2 + π‘βπ πππππππ 1 = 3 → 3 ÷ 2 = 1 πππππππππ 1 Write down the remainder 1 and ‘carry’ 1 to the next column to the left and write it down.. 1101 + 1111 11100 . 1111 (carried 1’s) Now multiply 32 by 1 Before we start multiplying we write down 0 under the first column since 1 is in the second column as shown above. 32 × 14 233 0 Change 11100π‘π€π to base ten. 11100π‘π€π 11100π‘π€π 11100π‘π€π 11100π‘π€π 11100π‘π€π = 1 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 0 × 20 = 1 × 24 + 1 × 23 + 1 × 22 + 0 × 21 + 0 × 20 = 1 × 16 + 1 × 8 + 1 × 4 + 0 × 2 + 0 × 1 = 16 + 8 + 4 + 0 + 0 = 28 1 × 2 = 2 → 2 ÷ 5 = 0 πππππππππ 2 So we write the remainder 2 and ‘carry’ 0 (nothing) to the left as shown above. 32 13 Method 1 105 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM × Call 0977-747000, 14 233 20 Mathematics 8 - 9 0968-747007, 0955-747000 First convert both numbers from base five to base ten, then multiply the two numbers in base ten and convert the answer to base 5. 1 × 3 = 3 → 3 ÷ 5 = 0 πππππππππ 3 So we write the remainder 3 as shown above 32 × 14 233 320 . Next, we do the addition. Change to base 10. When converting from base 5 to base 10: Step 1 Multiply the first digit (from the right) by 50 = 1 Step 2 Multiply the second digit (from the right) by 51 = 5 Step 3 Multiply the third digit (from the right) by 52 = 25 Step 4 Multiply the fourth digit (from the right) by 53 = 125 Keep increasing the power of 5 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). Looking at the first column: 3 + 0 = 3 → 3 ÷ 5 = 0 πππππππππ 3 Write down the remainder 3. 32 × 14 233 + 320 3 32πππ£π = 3 × 51 + π × 50 = 3×5+π×1 = 15 + π = 17 Looking at the second column: 3 + 2 = 5 → 5 ÷ 5 = 1 πππππππππ 0 Write down the remainder 0 and ‘carry’ 1. 32 × 14 233 + 320 03 14πππ£π = 1 × 51 + π × 50 = 1×5+π×1 =5+π =9 32πππ£π × 14πππ£π = 17 × 9 = 153 Looking at the third column: 2+3 = 5 5 + ′πππππππ ′ 1 → 6 ÷ 5 = 1 πππππππππ 1 Write down the remainder 1, and ‘carry’ the 1 to the column on the left. Since their no other numbers to add, just write the 1 in the fourth column. 32 × 14 233 + 320 1103 Change 153 from base 10 to base five. 153 ÷ 5 = 30 30 ÷ 5 = 6 6÷5= 1 1÷5= 0 πππππππππ π πππππππππ π πππππππππ π πππππππππ π Write the remainders from bottom up. That will give us 1103πππ£π Therefore, 32πππ£π × 14πππ£π = 17 × 9 = 153 = 1103πππ£π 32πππ£π × 14πππ£π = 1103πππ£π Method 2 106 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 = 75 + 5 + 0 310πππ£π = 80 14 Method 1 Subtract in base 5, then convert the answer to base 10. 1022 − 212 310 Method 2 First convert both numbers from base five to base 10, then add the two numbers (which are already in base 10). 1022πππ£π = π × 53 + π × 52 + π × 51 + π × 50 = π × 125 + π × 25 + π × 5 + π × 1 = 125 + π + ππ + π 1022πππ£π = 137 Subtract the first column on the right. 2 − 2 = 0. 0 divided by 5 (since this is base 5) = 0 remainder 0. So we write 0 and ‘carry’ nothing to the left. 212πππ£π = π × 52 + π × 51 + π × 50 =2×5×5+1×5+2×1 = 2 × 25 + 5 + 2 = 50 + 7 = 57 Now subtract the two numbers => 1022πππ£π − 212πππ£π => 137 − 57 => 80 Subtract the second column from the right 2 − 1 = 1. 1 divided by 5 = 0, remainder 1. So we write 1. Subtract the third column from the right 0 − 2=?. ‘Borrow’ 1 (which is 5) from the fourth column and add to 0 to make it 5. Then we will have: 5−2=3 3 divided by 5 = 0 remainder 3. So we write 3. 15 [2017.P1.Q22] Convert 10.1112 to base 10. First change the bicimal to fraction. [A bicimal is the base-two analog of a decimal; it has a bicimal point and bicimal places, and can be terminating or repeating.] 10111π‘π€π 10.111π‘π€π = 1000π‘π€π Note! Dividing by 1000 in whatever base results in the point moving three steps to the left. Now change the numerator and denominator to base 10. When converting from base 2 to base 10: Step 1 Multiply the first digit (from the right) by 20 = 1 Step 2 Multiply the second digit (from the right) by 21 = 2 Step 3 Multiply the third digit (from the right) by 22 = 4 Step 4 Multiply the fourth digit (from the right) by 23 = 8 Step 5 Multiply the fourth digit (from the right) by 24 = 16 The answer is 310πππ£π Change to base 10. When converting from base 5 to base 10: Step 1 Multiply the first digit (from the right) by 50 = 1 Step 2 Multiply the second digit (from the right) by 51 = 5 Step 3 Multiply the third digit (from the right) by 52 = 25 Step 4 Multiply the fourth digit (from the right) by 53 = 125 Keep increasing the power of 5 until all the digits in a number are multiplied. Step 5 Add all the products in step 1 to step 4 (depending on the number of digits the number has). 310πππ£π = π × 52 + π × 51 + π × 50 = 3×5×5+1×5+0×1 = 3 × 25 + 1 × 5 + 0 × 1 107 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 2 ÷ 2 = 1 πππππππππ π 1 ÷ 2 = 0 πππππππππ π Write the remainders from bottom up. That will give us 1001π‘π€π Keep increasing the power of 2 until all the digits in a number are multiplied. Step 6 Add all the products in step 1 to step 4 (depending on the number of digits the number has). 4 3 2 9 = 1001π‘π€π 110110π‘π€π ÷ 110π‘π€π = 54 ÷ 6 =9 = 1001π‘π€π 1 10111π‘π€π = 1 × 2 + 0 × 2 + 1 × 2 + 1 × 2 + 1 × 20 11011π‘π€π = 1 × 16 + 0 × 8 + 1 × 4 + 1 × 2 + 1 ×1 11011π‘π€π = 16 + 0 + 4 + 2 + 1 11011π‘π€π = ππ 17 1000π‘π€π = 1 × 23 + 0 × 22 + 0 × 21 + 0 × 20 1000π‘π€π = 1 × 8 + 0 × 4 + 0 × 2 + 0 × 1 1000π‘π€π = 8 + 0 + 0 + 0 1000π‘π€π = 8 Therefore, 10.111π‘π€π = 16 Multiply in base five (each time dividing by five and writing down the remainders). 34 × 23 212 + 1230 1442 34πππ£π × 23πππ£π = 1442πππ£π 10111π‘π€π 23 = = 2.875 1000π‘π€π 8 [2017.P2.Q2b] πΈπ£πππ’ππ‘π 110110π‘π€π ÷ 110π‘π€π , πππ£πππ π¦ππ’π πππ π€ππ ππ πππ π π‘π€π. 110110π‘π€π ÷ 110π‘π€π Mathematics 8 - 9 0968-747007, 0955-747000 19 SEQUENCES 1 Note that the difference between two consecutive numbers is increasing by 2. 9−5=π 15 − 9 = π 23 − 15 = π π₯ − 23 = ππ π¦ − π₯ = ππ 110110π‘π€π = = 1001π‘π€π 110π‘π€π Or convert both to base ten, divide, then change the answer back to base two. 110110π‘π€π = 1 × 25 + 1 × 24 + 0 × 23 + 1 × 22 + 1 × 21 + 0 × 20 110110π‘π€π = 1 × 32 + 1 × 16 + 0 × 8 + 1 × 4 + 1 ×2+0×1 110110π‘π€π = 32 + 16 + 0 + 4 + 2 + 0 = ππ Find π₯ πππ π¦ π₯ − 23 = 10 => π₯ = 10 + 23 = ππ π¦ − π₯ = 12 => π¦ − 33 = 12 => π¦ = 12 + 33 = ππ 110π‘π€π = 1 × 22 + 1 × 21 + 0 × 20 110π‘π€π = 1 × 4 + 1 × 2 + 0 × 1 110π‘π€π = 4 + 2 + 0 = π 110110π‘π€π ÷ 110π‘π€π = 54 ÷ 6 = 9 A Change 9 to base 2 9 ÷ 2 = 4 πππππππππ π 4 ÷ 2 = 2 πππππππππ π 33, 45. 2. 5, 6, 8, 11, 15,…. 108 Answer. FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 1 π − 10 = π 2 π π 10 − π₯ = π π Find π₯ π 10 − π₯ = π π 1 −π₯ = 2 − 10 2 1 −π₯ = −7 2 Divide both sides by −1 1 π₯=7 2 Notice that the difference between two numbers is increasing by 1. 12 6−5 =1 8−6 =2 11 − 8 = 3 15 − 11 = 4 π₯ − 15 = 5 Find π₯ π₯ − 15 = 5 π₯ = 5 + 15 π₯ = 20 The next term is 20 3 20 PYTHAGORAS’ THEOREM 1 1+1 =2 2+2 =4 4+3 =7 7 + 4 = 11 11 + 5 = 16 16 + 6 = 22 So 1,2,4,7,11,16, 22 1 Since this is a right triangle, use Pythagoras’ theorem. π΄π΅2 + π΅πΆ 2 = π΄πΆ 2 82 + π΅πΆ 2 = 102 64 + π΅πΆ 2 = 100 π΅πΆ 2 = 100 − 64 π΅πΆ 2 = 36 √π΅πΆ 2 = √36 π΅πΆ = 6 ππ 4. Note that the there is a common difference between two consecutive numbers. 4−1=π 7−4= π 10 − 7 = π π₯ − 10 = π Find π₯ π₯ − 10 = π π₯ = 3 + 10 π₯ = 13 2 Since ABD is a right triangle, use Pythagoras’ theorem. π΄π·2 + π΅π· 2 = π΄π΅2 π΄π·2 + 52 = 132 π΄π·2 + 25 = 169 π΄π·2 = 169 − 25 π΄π·2 = 144 √π΄π·2 = √144 AD = 12cm 5. Note that the there is a common difference between two consecutive numbers. 1 π 3 Triangle CBA and triangle DCA are right triangles. Use Pythagoras’ theorem to find AC and AD. π΄πΆ 2 = π΅πΆ 2 + π΄π΅2 π΄πΆ 2 = 42 + 32 20 − 17 = π 2 π 1 π 17 − 15 = π 2 π 1 π 15 − 12 = π 2 π 109 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, π΄πΆ 2 = 16 + 9 π΄πΆ 2 = 25 π΄π·2 π΄π·2 π΄π·2 π΄π·2 Mathematics 8 - 9 0968-747007, 0955-747000 21 BEARINGS = π΄πΆ 2 + πΆπ·2 = 25 + 122 = 25 + 144 = 169 1 The bearing of B from A is the clockwise angle from the North of A to the line joining A and B. Draw a North at A and B. The bearing of B from A is 120°. √π΄π·2 = √169 π΄π· = 13 The bearing of A from B is the clockwise angle from the North of B to the line joining B and A. 4 ππ = ππ = ππ = 9 ππ (sides of a square) ππ 2 + ππ 2 = ππ 2 (ππ¦π‘βππππππ π‘βπππππ) ππ 2 + 92 = 152 ππ 2 = 152 − 92 ππ 2 = 225 − 81 ππ 2 = 144 πβπ πππππππ ππ π΄ ππππ π΅ = 120° + 180° = 300° √ππ 2 = √144 ππ = 12 ππ ππ = ππ + ππ ππ = 9 ππ + 12 ππ ππ = 21 ππ 5 Use Pythagoras theorem. It states that the square of the hypotenuse (the side opposite the right angle) is equal to the sum of the squares of the other two sides. π2 = π 2 + π 2 152 = π€ 2 + 92 152 − 92 = π€ 2 225 − 81 = π€ 2 144 = π€ 2 2 The bearing of B from A is the clockwise angle from the North of A to the line joining A and B. Draw a North at A and B. The bearing of B from A is 120°. √144 = √π€ 2 12 = π€ π€ = 12 π The bearing of A from B is the clockwise angle from the North of B to the line joining B and A. πβπ πππππππ ππ π΄ ππππ π΅ = 120° + 180° = 300° 6 Use Pythagoras’ theorem to find BC. π΅πΆ 2 π΅πΆ 2 π΅πΆ 2 π΅πΆ 2 = ππΆ 2 + π΅π2 = 52 + 122 = 25 + 144 = 169 √π΅πΆ 2 = √169 π΅πΆ = 13ππ 110 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 straight line at Q = 180°. 3 The bearing of Q from P is the clockwise angle from the North of P to the line joining P and Q. Draw a North at P. πβπ πππππππ ππ π ππππ π = 77° + 180° = 257° π΅ππππππ ππ π ππππ π = 180° + 80° = 260° 22 EQUATIONS 3y – 20 = 7 3y − 20 + 20 = 7 + 20 Adding 20 to both sides of the equation is the same as taking − 20 to the other side and changing its sign from negative to positive. 3y = 7 + 20 3π¦ = 27 Divide both sides by 3. 3π¦ 27 = 3 3 π¦=9 1 2 First expand the brackets. π₯ − 8 = 3(4 − π₯) π₯ − 8= 3×4−3×π₯ π₯ − 8 = 12 − 3π₯ Move all the terms with π₯ to one side of the equal sign. The sign changes when a number crosses the equal sign. π₯ + 3π₯ = 12 + 8 4π₯ = 20 divide both sides by 4 4π₯ 20 = 4 4 π₯=5 Note: The bearing of P from Q is the clockwise angle from the North of Q to the line joining Q and P. π΅ππππππ ππ π ππππ π = 080° 4 The bearing of P from Q is the clockwise angle from the North of Q to the line joining P and Q. Take note of the alternate angles = 77° and the 111 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 3π¦ − 10 = 2 3π¦ = 2 + 12 3π¦ = 14 3π¦ 14 = 3 3 2 π¦=4 3 3 2π₯ + 13 = 3. 2π₯ = 3 − 13 2π₯ = −10 2π₯ −10 = 2 2 π₯ = −5 8 2 3 = π π+2 cross multiply 3π = 2(π + 2) 3π = 2π + 2 × 2 3π = 2π + 4 3π − 2π = 4 π=4 4 3(2π₯ + 1) = 17 − 2(π₯ − 1) multiply the brackets 3 × 2π₯ + 3 × 1 = 17 − 2 × π₯ − 2 × −1 6π₯ + 3 = 17 − 2π₯ + 2 move all terms with π₯ to one side of = 6π₯ + 2π₯ = 17 + 2 − 3 8π₯ = 16 8π₯ 16 = 8 8 9 3(π¦ − 2) = 4(9 − π¦) π₯=2 (expand the brackets) 3×π¦−3×2=4×9−4×π¦ 5 3π¦ − 6 = 36 − 3π¦ 3 = 12 π cross multiply 3 = 12 × π put terms with π¦ on one side and numbers on the other side. When a term crosses the equal sign, the sign changes. 3 = 12π 3π¦ + 3π¦ = 36 + 6 3 12π = 12 12 1 =π 4 1 π= 4 6π¦ = 42 6 π΄ππππ’ππ’ππππ€π = π₯ π π€πππ‘π π΅π’ππππ = π₯ + 5 π π€πππ‘π πΆβππππ = π₯ + 5 + 10 π π€πππ‘π πΆβππππ πππ‘ = π₯ + 15 π π€πππ‘π 10 3(π₯ − 5) = 45 Expand the brackets by multiplying 3 with every term 7 3(π¦ − 2) − 4 = 2 3π¦ − 3 × 2 − 4 = 2 3π¦ − 6 − 4 = 2 3π₯ − 15 = 45 divide both sides by 6 6π¦ 42 = 6 6 π¦=7 inside the brackets. 3 × π₯ − 3 × 5 = 45 3π₯ = 45 + 15 3π₯ = 60 112 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 3π₯ 60 = 3 3 Mathematics 8 - 9 0968-747007, 0955-747000 2 2(π₯ − 1) > 3π₯ − 5 2 × π₯ − 2 × 1 > 3π₯ − 5 2π₯ − 2 > 3π₯ − 5 2π₯ − 3π₯ > 2 − 5 −π₯ > −3 Divide both sides by −1 (dividing an inequality by a π₯ = 20 11 [2017.P1.Q12] ππππ£π π‘βπ πππ’ππ‘πππ 3(π₯ − 4) = 5 Expand the brackets by multiplying 3 with every term inside the brackets. 3(π₯ − 4) = 5 negative number causes the inequality sign to change 3π₯ − 12 = 5 direction i.e. > becomes < and ≥ becomes ≤ 3π₯ = 5 + 12 −π₯ −3 < −1 −1 3π₯ = 17 π₯<3 3π₯ 17 = 3 3 2 π₯=5 3 12 3 All terms without π₯ must be on one side, 7 + 2π₯ > 5 2π₯ > 5 − 7 2π₯ > −2 2π₯ −2 > 2 2 π₯ > −1 [2017.P2.Q2(a)] Solve the equation π₯ π₯ + =5 2 3 3π₯ + 2π₯ =5 6 5π₯ =5 6 4 First, change the inequality to equation by replacing the inequality signs with the equal sign π₯ + π¦ ≤ −2 → π₯ + π¦ = −2, 5π₯ = 5 × 6 5π₯ = 30 5π₯ 30 = 5 5 Second, draw the line of the equations π₯ + π¦ = −2, Find two points through which the line passes. (Pick reasonable values at random). π₯=6 π₯ + π¦ = −2 π€βππ π₯ = 0, (0, −2) 0 + π¦ = −2 => π¦ = −2 π€βππ π₯ = −5, −5 + π¦ = −2 => π¦ = 5 − 2 => π¦ = 3 (−5,3) Draw a line passing through (0, −2) and (−5,3) 23 INEQUATIONS 1 Horizontal lines are ′π¦′ equations. Vertical lines are ′π₯′ equations. The line crosses the π¦ − ππ₯ππ where π¦ = 2. Therefore, the equation is π¦ = 2. The shaded area is less than 2. Because the line is not continuous, there will be no equal sign in the inequality. The answer is π < π. Note that if the line was continuous, the inequality would be π¦ ≤ 2. Note that the line will be continuous (not dotted) if the inequality in question has the ‘or equal to’ component (≤ or ≥), meaning that values on the line are part of the wanted side. If the inequality sign is < or >, the 113 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, line will be dotted, meaning that points on the line are part of the unwanted side. π¦ > −4 Mathematics 8 - 9 0968-747007, 0955-747000 1 2 6 π − 4 > 3π + 8 π − 3π > 4 + 8 −2π > 12 Divide both sides by −2 (dividing an inequality by a negative number causes the inequality sign to change direction i.e. > becomes < and ≥ becomes ≤) −2π 12 < −2 −2 π < −6 Third step, find out which side of the line is unwanted. To know which side is unwanted (or wanted), choose a point on one side of the line and place the coordinate values into the inequality. For the line π₯ + π¦ = −2 , pick a point, say, (0,0) and place the values of π₯ and π¦ into the inequality. 0 + 0 ≤ −2. This does NOT satisfy the inequality π₯ + π¦ ≤ 0 because 0 is not less than −2. Therefore, this side of the line is unwanted, so shade the other side of the line as wanted. You pick another point from the other side (wanted region) to prove. Let’s pick (−5,0) 0 + (−5) ≤ −2 −5 ≤ −2 The above inequality is true because −5 < −2. So shade this wanted side of the line. 7 3π₯ + 12 > 7π₯ 3π₯ − 7π₯ > − 12 −4π₯ > −12 Divide both sides by −4 (dividing an inequality by a negative number causes the inequality sign to change direction i.e. > becomes < and ≥ becomes ≤) −4π₯ −12 < −4 −4 π₯<3 8 6π₯ − 13 > 11π₯ – 3 6π₯ − 11π₯ > 13 − 3 −5π₯ > 10 Divide both sides by −5 (dividing an inequality by a negative number causes the inequality sign to change direction i.e. > becomes < and ≥ becomes ≤) −5π₯ 10 < −5 −5 π₯ < −2 5 π¦ − 4 < 5 + 3π¦ π¦ − 3π¦ < 5 + 4 −2π¦ < 9 Divide both sides by −2 (dividing an inequality by a negative number causes the inequality sign to change direction i.e. > becomes < and ≥ becomes ≤) −2π¦ 9 > −2 −2 9 π₯ − 3(π₯ − 2) > 2 π₯ − 3 × π₯ − 3 × −2 > 2 π₯ − 3π₯ + 6 > 2 π₯ − 3π₯ > 2 − 6 −2π₯ > −4 Divide both sides by −2 (dividing an inequality by a negative number causes the inequality sign to change direction i.e. > becomes < and ≥ becomes ≤) 114 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, −2π₯ −4 < −2 −2 π₯<2 π¦ =π₯+1 π€βππ π₯ = 0, (0,1) π¦ = 0 + 1 => π¦ = 1 π€βππ π₯ = 2, π¦ =2+1 => π¦=3 (2,3) Draw a line passing through (0,1) and (2,3) 10 15 < − 4π₯ + 3 4π₯ < 3 − 15 4π₯ < −12 4π₯ −12 < 4 4 π₯ < −3 11 Mathematics 8 - 9 0968-747007, 0955-747000 Note that the line will be continuous (not dotted) if the inequality in question has the ‘or equal to’ component (≤ or ≥), meaning that values on the line are part of the wanted side. If the inequality sign is < or >, the line will be dotted, meaning that points on the line are part of the unwanted side. [2017.P1.Q29] Solve the inequation 8 + 3π₯ > 2 3π₯ > 2 − 8 3π₯ > −6 3π₯ −6 > 3 3 π₯ > −2 Third step, find out which side of the line is unwanted. To know which side is unwanted (or wanted), choose a point on one side of the line and place the coordinate values into the inequality. 12 [2017.P2.Q7(d)] Illustrate the solution of y ≥ x + 1 on the XOY plane shown below, by shading the wanted region, for the domain −3 ≤ x≤ 3. [3] For the line π¦ = π₯ + 1 , pick a point, say, (0,0) and place the values of π₯ and π¦ into the inequality. 0 ≥ 0 + 1. This does NOT satisfy the inequality π¦ ≥ π₯ + 1 because 0 is not greater than 1. Therefore, this side of the line is unwanted, so shade the other side of the line as wanted. You pick another point from the other side (wanted region) to prove. Let’s pick (0,2) π¦ ≥π₯+1 2≥0+1 The above inequality is true because 2 ≥ 1. So shade this wanted side of the line. First, change the inequality to equation by replacing the inequality signs with the equal sign π¦≥π₯+1 → π¦=π₯+1 24 SIMULTENEOUS EQUATIONS Second, draw the line of the equations π¦ = π₯ + 1, Find two points through which the line passes. (Pick reasonable values at random). 1 Elimination method 2π₯ − π¦ = 5, (1) π₯ + π¦ = 4 (2) 115 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, −3π¦ −3 = −3 −3 Make the coefficients of the variable you want to eliminate to be the same in both equations. π=π πππ€ π’π π π‘βπ π£πππ’π ππ π¦ = 1 The coefficient of π¦ in both equations is already the same. Since they have different signs (π¦ and −π¦), add equation (1) and (2) to eliminate π¦. ππ πππ’ππ‘πππ (1)ππ (2) π‘π ππππ π‘βπ π£πππ’π ππ π₯. π₯ + π¦ = 4, (2) ππ πππ’ππ π‘βππ‘ π¦ = 1 π₯ + 1 = 4 2π₯ − π¦ = 5, π₯ + π¦ = 4, 2π₯ + π₯ − π¦ + π¦ = 5 + 4 π₯ =4−1 3π₯ + 0 = 9 3π₯ = 9 3π₯ 9 = 3 3 π₯=3 π₯=3 We now have π = 3, π=π NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. To find π¦, replace π₯ in equation (1) or (2) π₯ + π¦ = 4 (π₯ = 3) 3+ π¦ = 4 Mathematics 8 - 9 0968-747007, 0955-747000 (2) 2π₯ − π¦ = 5 (2) π = 3, π=π 2(3) − 1 = 5 6 − 1 = 5 π‘ππ’π π π‘ππ‘πππππ‘ π¦ = 4−3 π¦=1 π = π, π=1 2 [2015.P2.Q2(b)] Solve the simultaneous equations 3π₯ − 2π¦ = 12, π₯ + 3π¦ = −7 Substitution method Take one equation and make one letter the subject of the formula. 2π₯ − π¦ = 5, (1) π₯ + π¦ = 4 (2) Elimination method 3π₯ − 2π¦ = 12, π₯ + 3π¦ = −7 Take equation (2) and make π₯ the subject of the formula. (1) (2) Make the coefficients of the variable you want to eliminate to be same in both equations. To eliminate π₯, multiply equation (2) by 3 so that the coefficient of π₯ in both equations is 3. π₯ + π¦ = 4 (2) π₯ = 4−π¦ ππ’ππ π‘ππ‘π’π‘π π₯ ππ π‘βπ ππ‘βππ πππ’ππ‘πππ, πππ’ππ‘πππ (1) ππ π‘βππ πππ π, π€ππ‘β 4 − π¦ 3π₯ − 2π¦ = 12, (1) 3π₯ + 9π¦ = −21, (3) 2π₯ − π¦ = 5, (1) 2(4 − π¦) − π¦ = 5 Subtract equation (3) from equation (1) 3π₯ − 3π₯ − 2π¦ − 9π¦ = 12 − (−21) 8 − 2π¦ − π¦ = 5 −3π¦ = 5 − 8 −11π¦ = 33 −3π¦ = −3 116 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 −11π¦ 33 = −11 −11 −11π¦ 33 = −11 −11 π¦ = −3 π = −π πππ€ π’π π π‘βπ π£πππ’π ππ π¦ = −3 To find π₯, replace π¦ in equation (1) or (2) πππ’ππ‘πππ (1)ππ (2) π‘π ππππ π‘βπ π£πππ’π ππ π₯. 3π₯ − 2π¦ = 12, (1) π¦ = −3 3π₯ − 2(−3) = 12 3π₯ − 2π¦ = 12, (1) ππ πππ’ππ π‘βππ‘ π¦ = −3 3π₯ − 2(−3) = 12 3π₯ + 6 = 12 3π₯ + 6 = 12 3π₯ = 12 − 6 3π₯ = 12 − 6 3π₯ = 6 3π₯ = 6 3π₯ 6 = 3 3 π₯=2 π₯ = 2, π¦ = −3 ππ 3π₯ 6 = 3 3 π₯=2 ans. NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. We now have 3π₯ − 2π¦ = 12, (1) π₯ = 2, π¦ = −3 3(2) − 2(−3) = 12 6 + 6 = 12 NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. π = 2, π = −π Substitution method 3π₯ − 2π¦ = 12, (1) π₯ = 2, π¦ = −3 3(2) − 2(−3) = 12 6 + 6 = 12 π‘ππ’π π π‘ππ‘πππππ‘ Take one equation and make one letter the subject of the formula. 3π₯ − 2π¦ = 12, (1) π₯ + 3π¦ = −7. (2) 3 ECZ-2013-P2-Q6(a) Solve the simultaneous equations π₯ + π¦ = 0, 3π₯ − π¦ = −8. [3] Take equation (2) and make π₯ the subject of the formula. Solution Substitution method π₯ + 3π¦ = −7 (2) π₯ = −3π¦ − 7 ππ’ππ π‘ππ‘π’π‘π π₯ ππ π‘βπ ππ‘βππ πππ’ππ‘πππ, πππ’ππ‘πππ (1) ππ π‘βππ πππ π, π€ππ‘β − 3π¦ − 7 Take one equation and make one letter the subject of the formula. π₯ + π¦ = 0, (1) 3π₯ − π¦ = −8 (2) 3π₯ − 2π¦ = 12, (1) 3(−3π¦ − 7) − 2π¦ = 12 Take equation (1) and make π₯ the subject of the formula. −9π¦ − 21 − 2π¦ = 12 −9π¦ − 2π¦ = 12 + 21 π₯ + π¦ = 0, (1) π₯ = −π¦ ππ’ππ π‘ππ‘π’π‘π π₯ ππ π‘βπ ππ‘βππ πππ’ππ‘πππ, πππ’ππ‘πππ (2) −11π¦ = 33 117 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 ππ π‘βππ πππ π, π€ππ‘β − π¦ π₯ = −2 3π₯ − π¦ = −8 (2) 3(−π¦) − π¦ = −8 To find π¦, replace π₯ in equation (1) or (2) π₯ + π¦ = 0 (1) (π₯ = −2) −2 + π¦ = 0 −3π¦ − π¦ = −8 −4π¦ = −8 −4π¦ −8 = −4 −4 π¦=2 π = −π, π=2 π=π πππ€ π’π π π‘βπ π£πππ’π ππ π¦ = 2 ππ πππ’ππ‘πππ (1)ππ (2) π‘π ππππ π‘βπ π£πππ’π ππ π₯. 4 Substitution method π₯ + π¦ = 0, (1) ππ πππ’ππ π‘βππ‘ π¦ = 2 π₯ + 2 = 0 Take one equation and make one letter the subject of the formula. 3π₯ + 4π¦ = 32, (1) π₯ = 4π¦ (2) π₯ = −2 We now have π = −2, Equation (2) already has π₯ as the subject of the formula π₯ = 4π¦ ππ’ππ π‘ππ‘π’π‘π π₯ ππ π‘βπ ππ‘βππ πππ’ππ‘πππ, πππ’ππ‘πππ (1) ππ π‘βππ πππ π, π€ππ‘β 4π¦ π=π NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. 3π₯ − π¦ = −8 (2) π = −2, π=π 3π₯ + 4π¦ = 32, (1) 3(4π¦) + 4π¦ = 32 3(−2) − 2 = −8 −6 − 2 = −8 π‘ππ’π π π‘ππ‘πππππ‘ 3 × 4π¦ + 4π¦ = 32 12π¦ + 4π¦ = 32 16π¦ = 32 Elimination method 16π¦ 32 = 16 16 π₯ + π¦ = 0, (1) 3π₯ − π¦ = −8 (2) π=π πππ€ π’π π π‘βπ π£πππ’π ππ π¦ = 2 Make the coefficients of the variable you want to eliminate to be the same in both equations. ππ πππ’ππ‘πππ (1)ππ (2) π‘π ππππ π‘βπ π£πππ’π ππ π₯. The coefficient of π¦ in both equations is already the same. Since they have different signs (π¦ and −π¦), add equation (1) and (2) to eliminate π¦. π₯ = 4π¦ (2) ππ πππ’ππ π‘βππ‘ π¦ = 2 π₯ = 4(2) π₯=8 π₯ + π¦ = 0, 3π₯ − π¦ = −8, π₯ + 3π₯ + π¦ + −π¦ = 0 + (−8) 4π₯ + 0 = −8 4π₯ = −8 4π₯ −8 = 4 4 We now have π = 8, π=π NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. 118 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 3π₯ + 4π¦ = 32 π = 8, π=π Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 (1) To eliminate π₯, multiply equation (1) by the coefficient of π₯ in equation (2) i.e. 1, and multiply equation (2) by the coefficient of π₯ in equation (1) i.e. 3, so that the coefficient of π₯ in both equations is 3 × 1 = 1 × 3 = 3. 3(8) + 4(2) = 32 24 + 8 = 32 π‘ππ’π π π‘ππ‘πππππ‘ Elimination method 1 × [3π₯ + 4π¦ = 32], 3 × [ π₯ − 4π¦ = 0 ], 3π₯ + 4π¦ = 32, (1) π₯ = 4π¦ (2) re-arrange equation (2) into the form of (1) 3π₯ + 4π¦ = 32, (1) π₯ − 4π¦ = 0 (2) 1 × 3π₯ + 1 × 4π¦ = 1 × 32, 3 × π₯ + 3 × −4π¦ = 3 × 0, 3π₯ + 4π¦ = 32, 3π₯ − 12π¦ = 0, Make the coefficients of the variable you want to eliminate to be the same in both equations. Subtract the like terms in second equation from the first. This results in the elimination of π₯. (If you want to eliminate π¦, make the coefficients of π¦ to be the same.) The coefficient of π¦ in both equations is already the same. Since they have different signs (4π¦ and −4π¦), add equation (1) and (2) to eliminate π¦. Subtract equation (2) from equation (1) to eliminate π₯ 3π₯ + 4π¦ = 32, 3π₯ − 12π¦ = 0, 3π₯ − 3π₯ + 4π¦ − (−12π¦) = 32 − 0 3π₯ + 4π¦ = 32, π₯ − 4π¦ = 0, 3π₯ + π₯ + 4π¦ + (−4π¦) = 32 + 0 4π₯ + 0 = 32 4π₯ = 32 4π₯ 32 = 4 4 π₯=8 0 + 4π¦ + 12π¦ = 32 16π¦ = 32 16π¦ 32 = 16 16 π¦=2 To find π¦, replace π₯ in equation (1) or (2) πππ€ π’π π π‘βπ π£πππ’π ππ π¦ = 2 3π₯ + 4π¦ = 32 (1) π₯=8 3(8) + 4π¦ = 32 ππ πππ’ππ‘πππ (1)ππ (2) π‘π ππππ π‘βπ π£πππ’π ππ π₯. 4y = 32 − 24 π₯ = 4π¦ (2) ππ πππ’ππ π‘βππ‘ π¦ = 2 π₯ = 4(2) 4y = 8 π₯=8 4y 8 = 4 4 We now have 24 + 4π¦ = 32 π = 8, π=π π¦=2 π = π, NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. π=2 The answers can also be found by first eliminating π₯ 3π₯ + 4π¦ = 32 π = 8, π=π 3π₯ + 4π¦ = 32, π₯ − 4π¦ = 0, 3(8) + 4(2) = 32 119 (1) FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM 24 + 8 = 32 Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 3(2) − (−1) = 7 6+1 =7 π‘ππ’π π π‘ππ‘πππππ‘ π‘ππ’π π π‘ππ‘πππππ‘ 5 Substitution method Take one equation and make one letter the subject of the formula. π₯ + π¦ = 1, (1) 3π₯ − π¦ = 7 (2) Elimination method π₯ + π¦ = 1, 3π₯ − π¦ = 7 (1) (2) (1) (making π₯ the subject) Make the coefficients of the variable you want to eliminate to be the same in both equations. ππ’ππ π‘ππ‘π’π‘π π₯ ππ π‘βπ ππ‘βππ πππ’ππ‘πππ, πππ’ππ‘πππ (2) ππ π‘βππ πππ π, π€ππ‘β 1 − π¦ The coefficient of π¦ in both equations is already the same. Since they have different signs (−π¦ and +π¦), add equation (1) and (2) to eliminate π¦. π₯+π¦=1 π₯ =1−π¦ 3π₯ − π¦ = 7, (2) 3(1 − π¦) − π¦ = 7 π₯ + π¦ = 1, 3π₯ − π¦ = 7 , π₯ + 3π₯ + π¦ + (−π¦) = 1 + 7 4π₯ + 0 = 8 4π₯ = 8 4π₯ 8 = 4 4 π₯=2 3×1−3×π¦−π¦ = 7 3 − 3π¦ − π¦ = 7 3 − 4π¦ = 7 −4π¦ = 7 − 3 −4π¦ = 4 −4π¦ 4 = −4 −4 To find π¦, replace π₯ in equation (1) or (2) π¦ = −1 π₯ + π¦ = 1 (1) π₯=2 2+π¦ =1 π¦ = 1−2 y = −1 π = π, π = −1 πππ€ π’π π π‘βπ π£πππ’π ππ π¦ = −1 ππ πππ’ππ‘πππ (1)ππ (2) π‘π ππππ π‘βπ π£πππ’π ππ π₯. The answers can also be found by first eliminating π₯ π₯ + π¦ = 1, (1) ππ πππ’ππ π‘βππ‘ π¦ = −1 π₯ + (−1) = 1 π₯ + π¦ = 1, 3π₯ − π¦ = 7 , π₯−1=1 π₯ =1+1 To eliminate π₯, multiply equation (1) by the coefficient of π₯ in equation (2) i.e. 3, and multiply equation (2) by the coefficient of π₯ in equation (1) i.e. 1, so that the coefficient of π₯ in both equations is 1 × 3 = 3 × 1 = 3. π₯=2 We now have π = 2, π = −π NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. 3 × [π₯ + π¦ = 1], 1 × [3π₯ − π¦ = 7 ], 3π₯ − π¦ = 7 (2) π = 2, π = −π 3 × π₯ + 3 × π¦ = 3 × 1, 1 × 3π₯ − 1 × π¦ = 1 × 7, 120 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 π₯ + π¦ = 4. 3π₯ + 3π¦ = 3, 3π₯ − π¦ = 7, Elimination method Subtract the like terms in second equation from the first. This results in the elimination of π₯. (If you want to eliminate π¦, make the coefficients of π¦ to be the same.) 2π₯ + π¦ = 14,, (1) π₯ + π¦ = 4 (2) Make the coefficients of the variable you want to eliminate to be the same in both equations. Subtract equation (2) from equation (1) to eliminate π₯ 3π₯ − 3π₯ + 3π¦ − (−π¦) = 3 − 7 The coefficient of π¦ in both equations is already the same. Since they have same signs (+π¦ and +π¦), subtract equation (2) and (1) to eliminate π¦. 0 + 4π¦ = −4 4π¦ = −4 4π¦ −4 = 4 4 2π₯ + π¦ = 14, (1), π₯ + π¦ = 4 , (2) 2π₯ − π₯ + π¦ − π¦ = 14 − 4 π₯ + 0 = 10 π₯ = 10 π¦ = −1 πππ€ π’π π π‘βπ π£πππ’π ππ π¦ = −1 ππ πππ’ππ‘πππ (1)ππ (2) π‘π ππππ π‘βπ π£πππ’π ππ π₯. To find π¦, replace π₯ in equation (1) or (2) π₯+π¦ =4 (π₯ = 10) 10 + π¦ = 4 π¦ = 4 − 10 π¦ = −6 3π₯ − π¦ = 7 , (2) ππ πππ’ππ π‘βππ‘ π¦ = −1 3π₯ − (−1) = 7 3π₯ + 1 = 7 3π₯ = 7 − 1 π = ππ πππ π = −π 1 πβπππππ π πππ πππ‘ππ ππππ π πππ πππ’ππ π πππ 3π₯ = 6 3π₯ 6 = 3 3 π=π We now have π = π, π = −1 NB. Use these values of x and y in either equation (1) or (2) or both to prove your accuracy. 25 SIMILARITY & CONGRUENCY 6 [2017.P2.Q1(c)] Solve the simultaneous equations 2π₯ + π¦ = 14, 121 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 3π₯ 12 = 3 3 1 (i) The ratios of corresponding sides of similar triangles (or figures) are equal. ππ 8 ππ 8 ππ 8 OR: AR = = = = π΄π π΄π + ππ 16 ππ + 8 ππ 24 8 1 = 24 3 1 OR: AR = = 1: 3 3 x=4 LQ = 4 cm 3 B (i) and (iii) When two triangles are similar, the ratios of the corresponding sides are equal. The corresponding angles in similar triangles are equal. Find the missing angles in the triangles. The sum of angles in a triangle is 180°. As can be seen below, triangle (i) and (iii) have equal corresponding angles of 50°, 60° and 70°. (ii) The ratios of corresponding sides of similar triangles (or figures) are equal. RS ππ = AB ππ΄ RS 8 ππ = AB 16 ππ RS 1 = AB 2 RS: AB = 1: 2 2 The ratios of corresponding sides of similar triangles (or figures) are equal. LQ πΏπ = LN πΏπ LQ πΏπ = LQ + QN πΏπ + ππ 4 Triangles XQP and XZY are similar triangles because corresponding angles are equal. Therefore, the ratios of corresponding sides are equal. Let LQ = π₯ ππ ππππππ πππππ π‘π ππ ππ ππππππ πππππ π‘π ππ ππ ππππππ πππππ π‘π ππ ππ ππ ππ = = ππ ππ ππ π₯ 6 = π₯+2 6+3 π₯ 6 = π₯+2 9 make the subject of the formula. Pick the ratio of sides whose values are given. ππ ππ = ππ ππ 9 × π₯ = 6(π₯ + 2) 9π₯ = 6 × π₯ + 6 × 2 9π₯ = 6π₯ + 12 ππ 3 = ππ 3 + 2 9π₯ − 6π₯ = 12 3π₯ = 12 122 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, ππ 3 = ππ 5 πβπππππππ, Mathematics 8 - 9 0968-747007, 0955-747000 From the diagram above, we can see that all corresponding angles of triangle ABC and triangle DEC are equal. This means that triangle ABC and triangle DEC are similar triangles. The ratios of corresponding sides of similar triangles (or figures) are equal, π΄π΅ π΅πΆ = π·πΈ πΈπΆ ππ: ππ = 3: 5 5 Congruent triangles are triangles that have equal corresponding sides and equal corresponding angles. The following pairs of triangles are congruent. POS and QOR PQO and RSO PQR and RPS PSQ and QRS (π‘βπ π πππ π€π πππ πππ‘ππππ π‘ππ ππ ππ’π π‘ ππ πππππ’πππ) π΅πΆ = π΅πΈ + πΈπΆ π΄π΅ π΅πΈ + πΈπΆ = π·πΈ πΈπΆ 12 π΅πΈ + 5 = 4 5 ππππ π©π¬ π‘βπ π π’πππππ‘ ππ π‘βπ πππππ’ππ 4(π΅πΈ + 5) = 12 × 5 4π΅πΈ + 4 × 5 = 60 4π΅πΈ + 20 = 60 4π΅πΈ = 60 − 20 4π΅πΈ = 40 4π΅πΈ 40 = 4 4 π΅πΈ = 10 ππ 6 When two triangles are similar, the ratios of the corresponding sides are equal. The corresponding angles in similar triangles are equal. ππ ππππππ πππππ π‘π ππ ππ ππππππ πππππ π‘π π π ππ ππππππ πππππ π‘π ππ ππ ππ ππ = = ππ π π ππ 8 Two figures (triangles) are similar if the ratios of the lengths of their corresponding sides are equal or all corresponding angles are equal. Pick the ratio of sides whose values are given and one containing the side we looking for. ππ ππ = ππ π π From the diagram above, we can see that all corresponding angles of triangle XYZ and triangle XPQ are equal. This means that triangle XYZ and triangle XPQ are similar triangles. The ratios of corresponding sides of similar triangles (or figures) are equal, ππ ππ = ππ ππ (π‘βπ π πππ π€π πππ πππ‘ππππ π‘ππ ππ ππ’π π‘ ππ πππππ’πππ) π₯+2 15 = π₯ + 6 15 + 10 π₯ + 2 15 = π₯ + 6 25 cross multiply ππππ π π‘βπ π π’πππππ‘ ππ π‘βπ πππππ’ππ 25(π₯ + 2) = 15(π₯ + 6) 25π₯ + 25 × 2 = 15π₯ + 15 × 6 25π₯ + 50 = 15π₯ + 90 25π₯ − 15π₯ = 90 − 50 10π₯ = 40 ππ 30 = 18 20 ππ 3 = 18 2 cross multiply ππ × 2 = 3 × 18 ππ × 2 3 × 18 = 2 2 ππ = 3 × 9 ππ = 27ππ 7 123 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 10π₯ 40 = 10 10 π₯ = 4 ππ Mathematics 8 - 9 0968-747007, 0955-747000 Make use of the pair of corresponding sides with known values. πΆπ 3 = πΆπ΅ 3 + 6 πΆπ 3 = πΆπ΅ 9 πΆπ 1 = πΆπ΅ 3 πͺπΈ: πͺπ© = π: π 9 BC is opposite to 80° angle. The side in triangle QPR that is opposite to the 80° angle is QP. Therefore, QP corresponds to BC. 10 When two triangles are similar, the ratios of the corresponding sides are equal. ππ ππ = ππ ππ π₯+3 7 = π₯ 4 Note This means that the ratio of the other corresponding sides is also 1:3 ππ: π΄π΅ = 1: 3 4 × (π₯ + 3) = 7 × π₯ 14 When two triangles are similar, all the ratios of the corresponding sides are equal. The similar triangles are CPQ and CAB. π΄π· π·πΈ π΄πΈ = = π΄π΅ π΅πΆ π΄πΆ 4π₯ + 4 × 3 = 7π₯ 4π₯ + 12 = 7π₯ 4π₯ − 7π₯ = −12 −3π₯ = −12 Make use of the pair of corresponding sides with known values. πΏππ‘ π₯ = π΄π· −3π₯ −12 = −3 −3 π₯=4 π΄π· π·πΈ = π΄π΅ π΅πΆ π₯ 10 = π₯ + 4 15 11 BD is the side that is opposite to the 60° angle in the smaller triangle. The side that is opposite the 60° angle in the bigger triangle is AB. Therefore, AB corresponds to BD. 15π₯ = 10(π₯ + 4) 15π₯ = 10π₯ + 40 15π₯ − 10π₯ = 40 12 D AC and AE Other corresponding sides are: AB and AD BC and DE 5π₯ = 40 5π₯ 40 = 5 5 π₯ = 8ππ π΄π· = 8ππ 13 27 MATRICES When two triangles are similar, all the ratios of the corresponding sides are equal. The similar triangles are CPQ and CAB. πΆπ πΆπ ππ = = πΆπ΅ πΆπ΄ π΄π΅ 1 A matrix with m rows and n columns is called an m by n matrix (or m × n matrix). 124 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, The matrix D has 2 rows and 3 columns. Therefore, it is a 2 × 3 matrix. (ii) Multiplying a matrix by a number means multiplying every element in the matrix by the given number. In this case, every element in matrix A will be multiplied by 2. 3π = 3 × (5 −6 2) π Multiplying a matrix by a number means multiplying every element in the matrix by the given number. In this case, every element in matrix A will be multiplied by 3π = (3 × 5 3π = (15 6) −18 . 4 −8 ) 20 1 × 12 => (4 1 ×4 4 1 × (−8) 4 ) 1 × 20 4 => ( 5 Multiply every row in the first matrix by every column in the second matrix. 1 0 −2 1 × −2 + 0 × 5 ( )( ) = ( ) 0 1 5 0 × −2 + 1 × 5 3 −2 ) 1 5 ( 5 −4 2×2 3 )−( 2×3 2 ( 5 −4 4 3 )−( 6 2 ( 2×2 ) 2×3 π π π π )( π π π΄=( 4 ) 6 1 3 1 −10 −2 + 0 ) 0+5 =( −2 ) 5 3−4 ) 2−6 π ππ + ππ )=( π ππ + π π 2 5 ) πππ π΅ = ( 1 0 π΄π΅ = ( 1 3 π΄π΅ = ( 1×5+2×0 3×5+1×0 π΄π΅ = ( 5+0 15 + 0 π΄π΅ = ( 5 15 Now subtract corresponding elements. 5−4 −4 − 6 =( 6 Multiply every row in the first matrix by every column in the second matrix. π×π+π×π π×π+π×β π π π π ( )( )=( ) π×π+π×π π×π+π×β π π π β 3 Multiplying a matrix by a number means multiplying every element in the matrix by the given number. In this case, every element in matrix A will be multiplied by 2. 2 2 5 3 ( ) − 2( ) 3 3 −4 2 ( 3 × 2) 3 × −6 1 1 1 12 π¨= ( 4 4 4 ( Mathematics 8 - 9 0968-747007, 0955-747000 −1 ) −4 2 5 )( 1 0 ππ + ππ ) ππ + π π 0 ) 6 0 ) 6 1×0+2×6 ) 3×0+1×6 0 + 12 ) 0+6 12 ) 6 4 7 (i) A matrix with m rows and n columns is called an m by n matrix (or m × n matrix).The matrix N has 1 row and 3 columns. Therefore, it is a 1 × 3 matrix. (a) 1 x 3 matrix A matrix with m rows and n columns is called an m by n matrix (or m × n matrix).The matrix P has 1 row and 3 columns. Therefore, it is a 1 × 3 matrix. 125 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, 2 2π΄ − π΅ = 2 ( −3 4π = 4(−4 1 2) (b) 4π = (−16 4 8) Multiplying a matrix by a number means multiplying every element in the matrix by the given number. In this case, every element in matrix P will be multiplied by 4. 2×2 2 × −3 =( 4 −6 π π )( π π π΄=( π ππ + ππ )=( π ππ + π π 2 3 −1 ) πππ π΅ = ( 1 2 4 π΄π΅ = ( 2 1 3 −1 )( 2 4 π΄π΅ = ( 2 × −1 + 3 × 4 1 × −1 + 2 × 4 π΄π΅ = ( −2 + 12 −1 + 8 π΄π΅ = ( 10 7 2×0 3 )−( 2×5 4 0 3 )−( 10 4 1 ) −2 1 ) −2 4−3 −6 − 4 2π΄ − π΅ = ( 1 −10 0−1 ) 10 − −2 −1 ) 12 ππ + ππ ) ππ + π π 2 ) 3 2 ) 3 2×2+3×3 ) 1×2+2×3 4+9 ) 2+6 13 ) 8 9 πΊππ£ππ π‘βππ‘ 1 ) −2 Subtract corresponding elements 8 [2017.P2.Q2c] Multiply every row in the first matrix by every column in the second matrix. π×π+π×π π×π+π×β π π π π ( )( )=( ) π×π+π×π π×π+π×β π π π β π π 0 3 )−( 5 4 =( =( ( Mathematics 8 - 9 0968-747007, 0955-747000 2 π΄=( −3 πΉπππ 2π΄ − π΅. [2017.P2.Q3a] 0 3 1 ) πππ π΅ = ( ), 5 4 −2 [3] Multiplying a matrix by a number means multiplying every element in the matrix by the given number. In this case, every element in matrix A will be multiplied 28 COMPUTER STUDIES by 2. 126 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM Call 0977-747000, Mathematics 8 - 9 0968-747007, 0955-747000 1 Examples of computer output devices: monitor printer speaker projector head phones (Examples of input devices are: keyboards, mouse, scanner, microphone, camera, touchscreen monitor) 2 5 B 6 Mean is the average of numbers. 3 Keyboard. The rest are output devices. Other input devices are mouse, scanner and microphone. 4 Start Enter π Enter π π΄πππ = π ∗ π π·ππ ππππ¦ π΄πππ Stop Note. If you were asked to draw the flow for calculating and displaying Volume, it would look like one below. 29 PROBABILITY 1 127 FastLearn Examiner – available on CD for fast computer aided revision Online revision @ WWW.FASTLEARNEXAMINER.COM ππππππππππ‘π¦ = Call 0977-747000, ππ’ππππ ππ πππ£ππππππ ππ’π‘πππππ πππ π ππππ ππ’π‘πππππ ππππππππππ‘π¦ (πΊππππ) = ππ’ππππ ππ πΊππππ πππππ πππ‘ππ ππ’ππππ ππ πππππ 9 15 + 9 9 ππππππππππ‘π¦ (πΊππππ) = 24 3 ππππππππππ‘π¦ (πΊππππ) = 8 ππππππππππ‘π¦ (πΊππππ) = Note ππππππππππ‘π¦ (πβππ‘π) = ππ’ππππ ππ π€βππ‘π πππππ πππ‘ππ ππ’ππππ ππ πππππ ππππππππππ‘π¦ (πβππ‘π) = 15 15 + 9 ππππππππππ‘π¦ (πβππ‘π) = 15 24 ππππππππππ‘π¦ (πβππ‘π) = 5 8 2 ππππππππππ‘π¦ = ππ’ππππ ππ πππ£ππππππ ππ’π‘πππππ πππ π ππππ ππ’π‘πππππ ππππππππππ‘π¦ (π΅ππ’π) = ππ’ππππ ππ πππ’π πππππππ πππ‘ππ ππ’ππππ ππ πππππππ 3 3+6 3 1 ππππππππππ‘π¦ (π΅ππ’π) = = 9 3 ππππππππππ‘π¦ (π΅ππ’π) = 3 ππππππππππ‘π¦ = ππ’ππππ ππ πππ£ππππππ ππ’π‘πππππ πππ π ππππ ππ’π‘πππππ ππππππππππ‘π¦ (ππππππ) = ππ’ππππ ππ πππππππ πππ‘ππ ππ’ππππ ππ πππ’ππ‘π ππππππππππ‘π¦ (ππππππ) = 3 3 = 3+5 8 128 Mathematics 8 - 9 0968-747007, 0955-747000