Sing Yin Secondary School First Term Examination, 2013 – 2014 Mathematics 1 Form 3 Full marks: 100 Time allowed: 1.5 hours Answer ALL questions. Unless otherwise specified, all working must be clearly shown. The diagrams in this paper are not necessarily drawn to scale. Unless otherwise specified, numerical answers should either be exact or correct to 3 significant figures. 1. Convert 2 846 into a hexadecimal number. Show your steps. 2. Rationalize 3. Simplify 2 3 1 xy 2 xy 2 (3 marks) . (3 marks) 3 4. Simplify and express the answer with positive indices. (4 marks) 15 12 3 . (4 marks) 5. a Express 1.083 in the form of where a and b are positive integers. b 6. Simplify 7. The mode and the median of five integers a, b, c, d and e are 4 and 7 respectively, where a b c d e. (a) Write down the values of a, b and c. (b) Given that the mean of a, b, c, d and e is 6.6. Find the values of d and e. 5 1010 2.54 10 2014 1.35 10 2012 (4 marks) and express the answer in scientific notation. (5 marks) (6 marks) U 8. In the figure, PQRS is a parallelogram and QT is the angle bisector of PQR. QTU and USR are straight lines. TUS = 55. Find UTS. (4 marks) o 55 P T Q 9. S R S3X Class was asked how many times they visited the museum last year. The mean of the number of visits is 2.6 and the results are shown in the table below: Number of visits Number of people (a) (b) (c) (d) 1 7 2 10 3 8 4 n Find n. Write down the median number of visits. Write down the mode(s) number of visits. If another class S3Y of 40 students was asked the same question and the overall mean number of visits for two classes was 2.48, find the mean number of visits for S3Y. (6 marks) 10. Solve x 5 1 2x 3 or x 1 0 and represent the solution graphically. 11. Solve 5 x 5 x1 750 . (6 marks) (4 marks) F.3 First Term Exam, 2013-2014 Mathematics 1 P.2 of 3 A 12. In the figure, ABCD is a rectangle. AC and BD intersect at E. If DEC = 40 and AC = 10 cm, find the area of ABCD. (5 marks) D o E 40 C B 13. A rectangular flower bed has length (2x + 1) m and breadth 5 m. Its perimeter is greater than 14 m and its area is not greater than 65 m2. (a) Find the range of the values of x. (b) If the cost of fencing the flower bed is $320/m, what is the maximum cost for the fence? (6 marks) o 14. In the figure, ABCD is a rhombus and∠ABC = 65 . BC is produced to E such that CD = DE. AE and CD intersect at F. (a) Find ∠CDE. A 65 F o B (b) Find ∠DAE. (c) Is AE a perpendicular bisector of CD? 15. Evaluate D E C Explain your answer. (7 marks) 4n 4n1 . 4 n 2 (4 marks) 16. (a) Factorize x 3 8 . (b) Hence, or otherwise, factorize x 3 3x 2 . (5 marks) 17. The bacteria in a sample grows at a rate of r% per hour. At the beginning of the experiment, the number of bacteria in the sample was 20 000. Assuming that the bacteria did not die during the experiment. (a) Express the number of bacteria in terms of r after 2 hours. (b) Accidentally, 8 000 bacteria were added in the sample after 1 hour. As a result, there were 64 000 bacteria after two hours. Find the value of r. (7 marks) 18. In the figure, ABC is a triangle with AC = 15 and BC = 9. AB is produced to D such that and CD is an altitude. AD = a and BD = b. (a) Find the value of a2 – b2. (b) Given that AB = 8. (i) Find the value of a + b. (ii) Find the value of a. (8 marks) (b) 15 9 B A Prove that SBP QPC. S If SB = SR and RQ = QC, prove that PQRS is a rectangle. (9 marks) END OF PAPER **** Q 30 D A 30 60 B **** D R 19. In the figure, ABCD is a rectangle. AC cuts BD at P. SAB and BDQ are straight lines. BSP = DCQ = 30 and ABD = 60. (a) C P C F.3 First Term Exam, 2013-2014 Answers: 1. B1E(16) 2. 3 1 3. 8 y3 2 x3 4. 5. 9 5 13 1.08 3 12 3.77 10 2022 7a) a = b = 4, c = 7 7b) d = 8 and e = 10. 8. UTS = 55 9a) n = 10 9b) median = 3 9c) mode = 2 and 4 9d) m 2.375 10. x 1 6. 1 x3 11. 12. 32.1 (cm2) 13a) 1 <x≤6 2 13b) $11 520 14a) ∠CDE = 50o 14b) 32 .5 14c) AE is not a perpendicular bisector. 15. 12 16a) x 3 8 ( x 2)( x 2 2 x 4) x 3 3x 2 ( x 2)( x 1)2 17a) 20000 (1+ r%)2 b) r = 60. 18a) a 2 b2 144 16b) bi) a + b = 18 bii) a = 13 Mathematics 1 P.3 of 3