NAME: TEACHER: Your school name Year 10 Mathematics 2014 Examination Time: 2 hours Sections 1 Number Page number 2 2 Algebra 5 3 Graphs 8 MHJC Page 1 Result 2014 EOY Year 10 (104) 4 Measurement 11 5 Trigonometry 15 6 Geometry 19 7 Angles 24 8 Statistics 27 9 Probability 31 Answer ALL questions in the spaces provided in this booklet. Show ALL working. NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 1 Number Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only MHJC Page 2 2014 EOY Year 10 (104) Curriculum Level ========================================================================== (c) Tina’s parents pay for 500 mB of data on her new phone. Tina uses SKILLS QUESTIONS this up in 4 days! How much data will she need per month (30 days) if she uses it at this rate? QUESTION ONE Tina’s parents will finally let her get a smart phone. She wants a phone that costs $300. Her parents will only give her $75, enough to buy a budget model. (a) Tina decides to buy the $300 phone. What percentage of the cost does her parents’ money cover? ____________________________________ ____________________________________ (b) Tina sometimes babysits for $8/hr. How many hours of babysitting will she need to do to raise the extra money she needs for the phone? ____________________________________ ____________________________________ ____________________________________ ____________________________________ (d) 1 Gb of data is 1024 mB. The phone company Tina is with offers the following data packs: ● 3Gb for $50 ● 1 gB for $20 ● 500 mB for $10 and ● 50 mB for $6 Using your answer to part (c), what data packs should Tina buy to get a month’s data as cheaply as possible? Justify your answer. ____________________________________ ____________________________________ ____________________________________ ____________________________________ MHJC Page 3 2014 EOY Year 10 (104) ____________________________________ ____________________________________ (c) CheapSellaz holds a 20% off sale and lists the phone’s sales price as $782. What is their non-sale price for the phone? ____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________ QUESTION THREE Some students weighed their phones. Here are the weights (in g). Write them in order from smallest to largest: QUESTION TWO 110.7, 112.0, 110.08, 111.3, 110.309 A new smart phone has a recommended retail price of $1049. _______________________________________ (a) Shady Sam says he can get it for 65% of the recommended price. What is Shady Sam’s price? ____________________________________ ____________________________________ (b) Techfilla Company sells the phone at its recommended price…but then holds a “30% off everything sale”. What is the sale price of the phone? ____________________________________ ____________________________________ MHJC Page 4 2014 EOY Year 10 (104) QUESTION FOUR Tina’s teacher tells the class that they are not allowed to use their phones as calculators! Tina did not remember to bring her calculator to class. Show how these questions could be solved without a calculator (show working). ____________________________________ ____________________________________ 2 5 + 3 4 ____________________________________ (e) Find the lowest common multiple of 6 and 8. ____________________________________ (a) Find 20% of 800 (b) ____________________________________ = ____________________________________ (f) 5.2×103 × 4×105 ____________________________________ ____________________________________ ____________________________________ □ = 77 – 1 (c) 62 + ____________________________________ ____________________________________ ____________________________________ QUESTION FIVE Complete the rounding table Number Rounded to… Nearest 100 2 d.p. 4768.207 5211.367 4 59.0099 3 s.f. QUESTION SIX 3 (d) 2 − (4 + 2) + √16 ____________________________________ A phone cost a retailer $530 to get into the store. 72% profit is added to get the GST exclusive selling price, then 15% GST is added. (a) What will the GST inclusive selling price be? MHJC Page 5 2014 EOY Year 10 (104) ____________________________________ NCEA STYLE QUESTION ____________________________________ Tina hopes to save for an iPad, now that she has her phone. ____________________________________ (b) If the price in (i) is then discounted 30%, what will the new selling price be? ____________________________________ ____________________________________ Explain what you are calculating at each step. ● She now has a paper run. She delivers 430 papers twice per week at 5c per paper delivered. ● Her parents tell her that for every $5 she saves, they will give her $2 extra towards the ipad. ● The ipad cost 724 when she first starts saving. Its price will have come down by 15% by the time she is ready to go shopping. How long will it take Tina to save enough to buy the iPad? _______________________________________ (c) What is the percentage decrease between the original GST exclusive price and the discount price in (ii)? ____________________________________ ____________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ ____________________________________ (d) Another phone has a GST inclusive price of $870. What is the GST exclusive price? (GST is 15%) _______________________________________ _______________________________________ _______________________________________ ____________________________________ _______________________________________ ____________________________________ MHJC Page 6 _______________________________________ 2014 EOY Year 10 (104) _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ MHJC Page 7 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 2 Algebra Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only Curriculum Level ========================================================================== QUESTION ONE (a) These scales balance. Therefore, a bag weighs the same as how many blocks? ________________________________ MHJC Page 8 2014 EOY Year 10 (104) (b) If the first two scales are in perfect balance, what needs to be added (in place of the question mark) to balance the third set? QUESTION TWO Solve the following equations: (a) 10 + = 32 – 4 (b) 53 – = 41 (c) 2n + 5 = 29 _______________________________________ (d) 6n – 4 = 3n + 8 _______________________________________ _______________________________________ (e) 5(n – 3) = 35 _______________________________________ _______________________________________ (f) (n – 4)(n + 3) = 0 _______________________________________ QUESTION THREE Simplify the following expressions: (a) p × p × p × p MHJC Page 9 2014 EOY Year 10 (104) = ______________ (b) 4n – n = ______________ ___________________________________ (c) 5n + 4p – 3n + p = ______________ (d) 7n × 8n = ______________ (e) (3n4)2 = ______________ (f) (g) 2y 5 + (ii) How many biscuits will be needed for 20 people? ___________________________________ ___________________________________ (iii) How many people were there at the last party if they provided 175 biscuits? y 3 ________________________________ ___________________________________ ________________________________ ___________________________________ 14n4 x 35nx (b) The interest earned on an investment that pays interest annually can be calculated using the formula = ______________ QUESTION FOUR I= (a) To cater an afternoon tea, it was decided to provide 3 biscuits per person and supply an extra 10 biscuits in case of greedy people! The following formula was used: b = 3n + 10 P RT 100 Where I = amount of interest earned, P = “principal” (amount of money invested), R = the interest rate (as a %) and T = amount of time in years. (i) How much interest would be earned on a 3 year investment of $30 000 at 4% per annum? (i) Explain what b and n stand for ___________________________________ ___________________________________ ___________________________________ MHJC Page 10 2014 EOY Year 10 (104) ___________________________________ (ii) If $450 interest was earned on a 2 year investment of $2 400, what was the interest rate? ___________________________________ (g) (p – 6)2 + 6p ________________________________ ___________________________________ ________________________________ ___________________________________ QUESTION FIVE Expand the following, simplify if necessary. Fully factorise the following expressions (h) 5p + 10 = _______________________ (a) 5(b + c) = ________________________ (i) 42n – 12 = ______________________ (b) 12(n + 4) = ________________________ (j) x2 – 6x + 8 = ____________________ (c) p(5p + 1) = ________________________ ___________________________________ (d) n(6 – n) + 2(n + 3) QUESTION SIX For the following questions, write an algebraic equation that fits the problem. Solve it to find the answer. ___________________________________ ___________________________________ (a) Given that the angles in a triangle add to 180 degrees, what size (in degrees) is x in this triangle? (e) 4(y + 3) – 3(y – 1) ___________________________________ ___________________________________ __________________________________ (f) (x + 4)(x – 2) MHJC Page 11 2014 EOY Year 10 (104) ___________________________________ __________________________________ (b) Jessica is given $15 per week and also got $100 from her Grandma for her birthday. If all of this money is put into her bank account, how long has she been saving if she has $520? ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ (c) James’ two friends’ ages multiply to 154. One of them is two years older than James and one of them is one year younger than James. How old is James? ___________________________________ ___________________________________ ___________________________________ ___________________________________ (d) Find the sizes of both x and y, showing all working. ___________________________________ ___________________________________ ___________________________________ MHJC Page 12 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 3 Graphs Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only Curriculum Level ========================================================================== joining them in the order they are given. SKILLS QUESTIONS The first point and last point of each missing section has already been plotted. QUESTION ONE Part of a dot-to-dot graph picture is shown above, but two sections are missing. Complete them by plotting the points listed and MHJC Page 13 Section 1: (3, 1), (7, -2), (5, -3), (9, -7), (2, -7), (3, -10) Section 2: (-5, -3), (-7, -2), (-3, 1), (-6, 2), (0, 7) QUESTION TWO Give the next two terms in each of these patterns 2014 EOY Year 10 (104) (a) 6, 10, 14, 18, _____ , ______ (a) Complete the table for pattern numbers and numbers of matches. Pattern (P) 1 2 3 4 5 (b) 15, 30, 45, 60, ______ , ______ (c) 11, 8, 5, 2, ______ , ______ Matches (M) 4 7 (b) Write a rule linking the number of matches to the pattern number. (d) 4, 6, 10, 16, 24, _______ , _______ M = _____________________________ (e) n + 4, 2n + 1, 3n – 2, 4n – 5, _________, (c) How many matches would be required to make the tree that is Pattern number 23? _______________________________________ _____________ QUESTION THREE Ellen is already excited about Christmas and makes a Christmas tree pattern out of matches. _______________________________________ (d) What pattern number would require 244 matches to make? _______________________________________ _______________________________________ _______________________________________ (e) If the rule in part (b) was plotted on a graph, what would its y intercept be? _______________________________________ MHJC Page 14 2014 EOY Year 10 (104) QUESTION FOUR Colin believes his pattern is MUCH better than Ellen’s. 4 5 (c) Work out a rule that connects the number of squares required to the pattern number. _______________________________________ _______________________________________ _______________________________________ (a) Draw the pattern 4 tree. _______________________________________ _______________________________________ QUESTION FIVE (b) Complete the table showing the number of squares required for each pattern. Pattern (P) 1 2 3 MHJC Squares (S) 6 12 Give the gradients of the lines shown above (a) Gradient = __________ (b) Gradient = __________ Page 15 2014 EOY Year 10 (104) (c) Gradient = __________ At 2pm one day, Petra left her house to walk and visit Anna. Anna left her house to go on a walk. Kelly stayed home. The graph shows the three girls’ movements. QUESTION SIX (a) Give the equations of each girl’s line. Petra: Anna: Kelly: (b) How fast does Petra walk? ___________________________________ Here is the graph of the equation y = x 2 On the same grid, draw and label the graphs of (c) How far away from Anna does Kelly live? How is this shown on the graph? (a) y = x2 + 3 ___________________________________ (b) y = -x2 – 2 ___________________________________ (c) If all the points on the graph y = x2 were moved 1 unit to the right, give the equation of the new graph that would be formed. _______________________________________ _______________________________________ ___________________________________ (e) Explain why Anna and Petra do not necessarily meet each other. ___________________________________ QUESTION SEVEN MHJC (d) How fast does Anna walk? Page 16 2014 EOY Year 10 (104) ___________________________________ MHJC Page 17 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 4 Measurement Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only Curriculum Level ======================================================================== SKILLS QUESTIONS QUESTION ONE MHJC Page 18 2014 EOY Year 10 (104) ____________________ ____________________ (b) Cylinder _________________ _________________ (a) The dimensions of Cherie’s bath towel are given above. What is the area of Cherie’s towel? _________________ ________________________________________ _________________ (b) A towel weighs 500g per square metre. What does Cherie’s towel weigh? ________________________________________ ________________________________________ QUESTION TWO QUESTION THREE Cherie doesn’t like her bath too hot. She took the temperature of the bath water before and after adding some cold to it (thermometer reads in degrees Celsius). What were the temperature readings? Cherie is considering several different toothbrush holders. Calculate the volume of each one. (a) Rectangular prism (cuboid) ____________________ MHJC Page 19 2014 EOY Year 10 (104) (b) Unusually, Cherie’s bath is a prism (it does not get narrower, change shape or curve towards the bottom). If Cherie gets into the bath, the water level rises by 22 cm. What volume does the part of Cherie submerged by water have? ________________________________________ ________________________________________ First temperature: _________________ ________________________________________ Second temperature: ______________ ________________________________________ QUESTION FOUR Cherie’s bath is shaped like a semi-circle at either end. rectangle with a (a) If Cherie filled her bath right to the top, what would the surface area of the water be? (c) Cherie decides to fill her bath to a depth of 28 cm (without her in it!). She has read that her tap’s flow rate is 0.8 L/second. How long will it take her to fill her bath? QUESTION FIVE Give the conversions for these metric units: (a) 49 cm = _____________ m (b) 1.02 kg = ____________ g ________________________________________ (c) 154 mm = ____________ cm ________________________________________ (d) 24 mL = ______________ L ________________________________________ QUESTION SIX ________________________________________ Circle the most sensible measurement MHJC Page 20 (a) Width of a bathroom sink might be: 2014 EOY Year 10 (104) 47 m 47 cm 47 mm 47 L (b) A bath soap might weigh: 90 cm 90 kg 90 g 90 mg (c) Height of the bathroom door might be: 190 cm 190 kg 190 mm 190 m (d) The area of a face cloth might be: 625 m2 625 mL 625 cm2 625 mm MHJC Page 21 2014 EOY Year 10 (104) QUESTION SEVEN Cherie is planning to get a new surface covering for her bathroom floor. It is only laid on the shaded area of the floor plan (not under the bath area or vanity). All measurements are in mm. (a) What is the perimeter of Cherie’s whole bathroom? ________________________________________ ________________________________________ (c) Cherie’s flooring options are vinyl and laminate. Vinyl comes in 2m wide rolls and is priced at $90 for every linear metre, plus $120 laying costs. A single piece of vinyl would be used (leaving some excess “off-cuts”) Laminate costs $180/m2 of floor area. This price includes installation. Show (using calculations) which flooring option will be cheapest for Cherie. ________________________________________ ________________________________________ ________________________________________ ________________________________________ ________________________________________ (b) What is the area of the floor that is being resurfaced? ________________________________________ ________________________________________ MHJC Page 22 ________________________________________ ________________________________________ ________________________________________ QUESTION EIGHT 2014 EOY Year 10 (104) ________________________________________ QUESTION NINE Cherie’s friends know that she likes candles and soaps for her bathroom. (a) One friend gave her this soap, which is a trapezium prism. A toilet roll has the following dimensions: width of 11 cm, diameter of roll = 10 cm, diameter of cardboard tube = 4 cm. (a) What is the volume of paper in the roll? ________________________________________ ________________________________________ ________________________________________ (b) The roll has 200 sheets of toilet paper, each 12 cm long. If it was unrolled, what would the total area of the toilet paper be? ________________________________________ MHJC Page 23 (i) What is the area of one of the soap’s trapezium shaped faces? _____________________________________ _____________________________________ 2014 EOY Year 10 (104) (c) Cherie and her friends have started making “bath bombs”. These are spherical in shape and have a diameter of 7 cm. (ii) What is the volume of the soap? _____________________________________ (b) Cherie was also given this candle. It has a square base and is pyramid-shaped. (i) What is the volume of each “bath bomb”? _____________________________________ _____________________________________ (i) What is the volume of the candle? _____________________________________ _____________________________________ _____________________________________ (ii) Sadly, the candle broke into pieces before Cherie could light it. She melted down the wax and created a new candle shaped like a cube. What will the dimensions of the new candle be? _____________________________________ (ii) Cherie has a cuboid shaped container of bath bomb mix. Its length and width are 27 cm and 22 cm respectively. When the mixture is level, the container is filled to a depth of 10.4 cm. How many bath bombs can Cherie make? _____________________________________ _____________________________________ _____________________________________ _____________________________________ _____________________________________ MHJC Page 24 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 5 Trigonometry Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only Curriculum Level ========================================================================== SKILLS QUESTIONS ___________________________________ QUESTION ONE Use your calculator to find the values of n or A. Record your working. (a) 42 + 72 = n2 ___________________________________ ___________________________________ (d) 9 × n = cos 52 ___________________________________ (b) n2 + 82 = 122 MHJC (c) n = sin 35 × 8 Page 25 2014 EOY Year 10 (104) Complete this diagram for a different triangle. Use it to work out the size of side x. (e) 4 ÷ 7 = tan A ___________________________________ QUESTION TWO A teacher gave their student the following diagram to reinforce Pythagoras’ theorem. a2 + b2 = c2 The values inside the triangle are side lengths. MHJC Page 26 2014 EOY Year 10 (104) QUESTION THREE A boat is sailing due East of a radio beacon. A plane is due North of the beacon. The plane and boat are 18 km apart and the boat is 10 km from the beacon. _______________________________________ _______________________________________ _______________________________________ _______________________________________ QUESTION FOUR A windsurfer sails a course marked by three buoys that form a right-angled triangle. The first leg of the course is 35 m. Calculate x and y, the lengths of the other two legs. (a) How far North of the beacon is the plane? _______________________________________ _______________________________________ (b) What is the angle between the boat’s path and a path that would take it towards the plane? (The angle indicated on the diagram) _______________________________________ _______________________________________ (c) A bearing is an angle from north. Calculate the bearing of the boat from the plane’s position. MHJC Page 27 _______________________________________ 2014 EOY Year 10 (104) _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ QUESTION FIVE A kayak’s sail is shaped like an isosceles triangle. If it is 1.8 m wide at the top and the equal sides are 3 m, calculate the height of the sail. (b) Calculate A, the angle at the top of the mainsail. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ (c) Calculate y, a length on the smaller sail. QUESTION SIX _______________________________________ A boat has two right-angled triangle-shaped sails. The mainsail is 8m wide and the smaller sail is 12 m high. _______________________________________ _______________________________________ (a) Calculate x, the height of the mainsail. MHJC Page 28 2014 EOY Year 10 (104) QUESTION SEVEN A student tried to design a triangular windsurfing sail (these are usually curved!). The placement of the boom splits the sail into two right-angled triangles: ABC and BDC. AD = 4.2 m NB: this sail is unlikely to be practical in real life! (a) Calculate AB, the length of the sail from the top to the outer edge on the boom. _______________________________________ height. The base (BC) is 2.39 m, the perimeter of ABC is 8.2 m and the area of ABC is 1.61325 m2 . The angle CAB is 20o. Calculate the lengths of AB and BC. Clearly state what you are working out at each step and show your calculations. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ (b) Calculate angle CDB. (Hint, you may find that first calculating the length AC may help you). _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ QUESTION EIGHT _______________________________________ Triangle ABC is a non-right angled triangle. BD is its MHJC Page 29 _______________________________________ 2014 EOY Year 10 (104) QUESTION NINE The angle of elevation from a boat to a plane is 29o. The relative positions of the boat, plane and a radio beacon on the horizontal are given in the second diagram. Calculate the height (altitude) at which the plane is flying. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ MHJC Page 30 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 6 Geometry Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only Curriculum Level =========================================================================== QUESTION ONE (a) Draw a different octomino that has one line of symmetry. Here are three “octominoes”. An octomino is made of 8 squares, all of which are attached by a full side to at least one other square. These three all have one line of symmetry. (b) Draw an octomino that has two lines of symmetry and show these lines. MHJC Page 31 2014 EOY Year 10 (104) A different octomino is shown on the grid below. (c) Redraw this octomino to show what it would look like: (i) Rotated 90o clockwise about point P (ii) Reflected in the mirror-line m (iii) Enlarged by a scale factor of - 2 with centre P. QUESTION TWO An aeroplane has gone missing! Use compass constructions and shading to show the different areas that teams are searching. Label these loci A-C. (a) Team A is searching within 200 km of Irakleion. (b) Team B is searching all the places that are equal distance from Patra and Athens. (c) Team C was told that the plane had either been travelling from Izmir to Volos or from Izmir to Thessaloniki. They have been told to search along the path halfway between these two routes. MHJC Page 32 2014 EOY Year 10 (104) D = ___________________________ (d) Name the city that is nearly due North of Volos. __________________________________ QUESTION FOUR (e) Which city is approximately North-East of Athens? (a) How many cubes would it take to make this object? __________________________________ __________________ QUESTION THREE This Venn diagram was drawn up to group (b) Sketch an isometric drawing from the plan view below. quadrilaterals (4 sided shapes). Try to identify a quadrilateral for each of A – E. Note that if a label is outside a circle, it does not fit the description (e.g. D does NOT have parallel sides or right angles). A = ___________________________ B = ___________________________ C = ___________________________ MHJC Page 33 2014 EOY Year 10 (104) QUESTION FIVE QUESTION SIX In a fantasy computer game, there are many dangers. In this picture, 1 cm = 1 m. If you are within 3m of the cave, a dragon will attack you. If you get closer to the robot than to the cave, the robot will attack you. The wizard shoots his spells at you when you are within 5 m of him. Use compass constructions to show the places where you are threatened by two dangers. QUESTION SEVEN Sketch a net for a triangular prism. For the object above, the front view is drawn below. Draw the Right and Top views. MHJC Page 34 2014 EOY Year 10 (104) QUESTION NINE An octomino shaped like the number one is used to make a design. QUESTION EIGHT (a) This octomino has rotational symmetry. What is its order of rotation? The original shape is slightly darker than the others. Write a set of instructions for how to generate the WHOLE design step-by-step, using transformations. You may draw on and label and points or mirror lines you wish to use. You may find it helpful to number each “1” to show which order they should appear in. ____________________________ (b) Draw a different octomino that has rotational symmetry and state its order of rotation. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ MHJC Page 35 2014 EOY Year 10 (104) _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ MHJC Page 36 2014 EOY Year 10 (104) MHJC Page 37 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 7 Angles Answer ALL questions in the spaces provided in this booklet. Show ALL working For Assessor’s use only Curriculum Level ========================================================================== QUESTION ONE (a) Draw a cross inside one acute angle. (b) What size is angle ADC? ____________________________________ (c) The angle to the far right can be called ABC. Give another three letter name for this angle. ____________________________________ In the figure above… MHJC Page 38 2014 EOY Year 10 (104) (d) Put a tick inside an obtuse angle. (e) What would the angles inside the shape ABCD add to? ____________________________________ (c) Size of angle AOB? ___________________ (d) Size of angle BOC? ___________________ QUESTION THREE Give the size of the marked angles. Give a geometric reason for each one if you can. ____________________________________ QUESTION TWO (a) A = _________________ (a) Size of angle? _____________________ because _______________________________________ _______________________________________ (b) A = _________________ because _______________________________________ (b) Size of angle AOC? ___________________ MHJC Page 39 _______________________________________ 2014 EOY Year 10 (104) B = _________________ _______________________________________ because _______________________________________ _______________________________________ _______________________________________ _______________________________________ QUESTION FOUR _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ This diagram shows an isosceles triangle situated between parallel lines. QUESTION FIVE Calculate the size of angle E. You may need to first work out some of the angles marked a-d. Give a geometric reason and clearly identify each angle you calculate. _______________________________________ _______________________________________ _______________________________________ MHJC Page 40 2014 EOY Year 10 (104) _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ QUESTION SIX Calculate the size of angle A. You may need to calculate other angles in the diagram to do so. Label any angle that you use and give a geometric reason for its size. Complete the proof to show that ABC and ADE are similar triangles. Hint: You may need to extend the length of one of the existing lines. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ MHJC Page 41 2014 EOY Year 10 (104) QUESTION SEVEN Angles ABC and ADE are equal because: ______________________________________ ______________________________________ Angles ACB and AED are equal because: ______________________________________ ______________________________________ Angles BAC is also Angle ______________________________________ Because triangles ABC and ADE have ______________________________________ ______________________________________ Some triangles have been created by connecting points A, B, C on the circumference of a circle to the circle centre and also to each other. Each line to the centre is of equal length. Two of the angles in this diagram have been given. By calculating angles a-e (with geometric reasons), show that angle e is twice as big as angle ACB. they are similar triangles. a = __________ because ___________________ _______________________________________ b = __________ because ___________________ _______________________________________ MHJC Page 42 2014 EOY Year 10 (104) c = __________ because ___________________ QUESTION EIGHT _______________________________________ d = __________ because ___________________ _______________________________________ e = __________ because ___________________ _______________________________________ Conclusion: ____________________________ _______________________________________ Given that angle EBD is size x, give the sizes of the other angles in the triangle in terms of x. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ MHJC Page 43 2014 EOY Year 10 (104) _______________________________________ _______________________________________ _______________________________________ _______________________________________ MHJC Page 44 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 8 Statistics Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only Curriculum Level ========================================================================== QUESTION ONE _______________________________________ (a) Describe the _______________________________________ long-term trend in percentage of cars exceeding the speed limit in urban areas. MHJC Page 45 _______________________________________ 2014 EOY Year 10 (104) (b) Sam thinks the trends for the two speed limits show similar movements. What kind of graph could he use to look for a correlation between the two sets of data? _______________________________________ (c) Explain why the data for this graph is most likely based on samples. Suggest how it may have been collected. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ (d) Explain why we can’t use this graph to find how many cars exceeded the speed limit in 2011. Sam managed to obtain some data about car speeds in urban areas (where the speed limit is 50 km/h). (a) Is speed discrete or continuous data? _______________________________________ (b) How does the graph show that all speeds were rounded? What were they rounded to? _______________________________________ _______________________________________ _______________________________________ (c) Describe features of the distribution of speeds. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ (e) Estimate the percentage of cars that will break the rural speed limit in 2014. _______________________________________ _______________________________________ _______________________________________ QUESTION TWO MHJC Page 46 2014 EOY Year 10 (104) (d) In this sample, did the majority of cars stay within the speed limit? Give evidence for your claim. _______________________________________ _______________________________________ Mean Mode Lower quartile Upper quartile (c) Sketch a box plot of the data above the scale below _______________________________________ _______________________________________ _______________________________________ QUESTION THREE Sam’s school is loaned a speed radar which records car speeds to the nearest km/h. Sam uses it for 10 minutes at the school gate and records the following speeds: 52, 48, 55, 58, 53, 50, 49, 52, 53, 55, 59, 56, 51, 53, 53, 57, 54, 52, 56, 59, 51, 50, 49, 50, 53. (a) Create a dot plot for the data given above, using the scale below (d) Comment on whether Sam’s sample of cars is random. For what reasons might you question whether it is representative of all cars that pass by the school entrance? _______________________________________ _______________________________________ _______________________________________ _______________________________________ (b) Complete the table of summary statistics for the data. _______________________________________ _______________________________________ _______________________________________ Range Median MHJC QUESTION FOUR Page 47 2014 EOY Year 10 (104) Sam’s friend Katrina suggested that cars may travel faster than Sam thinks because they will slow down when they see the speed radar. She proposes an experiment: she and Sam will BOTH record the speed of the cars – Sam standing where he is clearly visible and Katrina 30 m away, hiding behind a bush. (a) Describe in words the relationship between the two speed readings. _______________________________________ _______________________________________ _______________________________________ _______________________________________ _______________________________________ QUESTION FIVE Sam decides to hold a survey to find out why a lot of people speed past the school entrance. He puts a survey in every letterbox he passes on his way home from school. The survey includes these questions: _______________________________________ 1. What speed do you normally drive at when passing Prince Albert High School? 2. How often do you break the speed limit? 3. Why do you break the speed limit? _______________________________________ Identify some problems with Sam’s sampling and question design. _______________________________________ _______________________________________ (b) Draw a line of best fit onto the points. (c) Using e vidence from the graph, comment on whether Katrina is correct that the cars travel slower past Sam (where they can see the radar) than they do past Katrina. _______________________________________ _______________________________________ MHJC Page 48 _______________________________________ _______________________________________ _______________________________________ _______________________________________ 2014 EOY Year 10 (104) _______________________________________ _______________________________________ _______________________________________ MHJC Page 49 2014 EOY Year 10 (104) NAME: TEACHER: YEAR 10 MATHEMATICS, 2014 Section 9 Probability Answer ALL questions in the spaces provided in this booklet. Show ALL working. For Assessor’s use only Curriculum Level ========================================================================== QUESTION ONE Put a dot on the scale to represent the likelihood of each event. (a) Your teacher has a cat that can tap-dance and speak Mandarin. (b) The next baby to be born in Auckland will be a boy. MHJC Page 50 (c) It will rain in your town sometime in the next fortnight. (d) All the kittens in a litter of 5 turn out to be males. 2014 EOY Year 10 (104) ____________________________________ QUESTION TWO Two superstitious models always pull one hairpin out of each other’s hairstyle for luck. (For each model, 12 the hair pins are black, 13 are brown and the rest, 16 , are silver). (a) List all the colour combinations possible (hint: black/brown and brown/black are two of them). ____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________ QUESTION THREE One study found that the probability of a female being left handed is 0.09, but for a male it is 0.12. (a) Complete the tree diagram for this situation (b) Calculate the probability that a randomly chosen person is female and left-handed. (b) What is the probability that both models get a black hairpin? ____________________________________ (c) What is the probability that the models get the same colour hairpin as each other? ____________________________________ ____________________________________ (d) Prove (showing calculations) that it is more likely to get two different colours than two colours the same. MHJC Page 51 ____________________________________ 2014 EOY Year 10 (104) ____________________________________ (c) Calculate the probability that a randomly chosen person is right-handed. ____________________________________ ____________________________________ (d) If three people are selected at random from the general population, what is the probability that all of them are left-handed males? ____________________________________ QUESTION FOUR Jeremy has a theory that toast is more likely to land with the butter side down. He tests this theory by dropping a piece of toast 50 times. ____________________________________ ____________________________________ (e) In a co-ed school (both genders attend) with 700 students, how many left-handers would we expect to have? ____________________________________ ____________________________________ (f) Identify at least one assumption we would have to make in order to calculate the answer to the previous question. (a) The toast lands butter side down 28 times. Use this to give an estimate (as a fraction in its simplest form) for the probability of toast landing butter side down. ____________________________________ (b) A group of schools got together to carry out 10 000 trials of this experiment. They found that the toast landed butter side down 6 248 times in their experiment. (i) Give an estimate for the probability of toast landing butter side down based on this experiment. ____________________________________ ____________________________________ ____________________________________ ____________________________________ MHJC Page 52 2014 EOY Year 10 (104) ____________________________________ (ii) Another group of schools decide to carry out 10 000 trials of buttered toast drops. Will they find that the toast lands butter side down 6248 times? Explain. ____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________ ____________________________________ (c) Which estimate (the one from Jeremy’s experiment or the one from the group of schools) is likely to be more accurate? Why? ____________________________________ ____________________________________ QUESTION FIVE An English teacher made a game involving two spinners. Students have to spin both spinners and put the parts together to make a “word”. Some “words” are not proper English. Each spinner has even-sized sections. (a) If you play the game, what is the probability of getting a word that ends in “ing”? ____________________________________ (b) How many “words” are possible? ____________________________________ (c) If you play the game and get a word ending in “ing”, what is the probability that it is a real word? ____________________________________ (d) Sarah gets hooked on the game and plays it a lot. If she has 5 turns, what is the probability that every “word” she makes begins with the letter b? ____________________________________ ____________________________________ ____________________________________ ____________________________________ MHJC Page 53 2014 EOY Year 10 (104) (e) Sarah then plays 100 games and gets either “coldest” or “colder” 25 times. Comment on whether this result seems unusual. ____________________________________ ____________________________________ MHJC Page 54 2014 EOY Year 10 (104) Year 10 Mathematics 2014 Examination Schedules Topics MHJC Number Page 1 Algebra Page 2 Patterns and Graphs Page 3 Measurement Page 4 Trigonometry Page 5 Page 55 2014 EOY Year 10 (104) MHJC Geometry Page 6 Angles Page 7 Statistics Page 9 Probability Page 10 Page 56 2014 EOY Year 10 (104) Section 1: NUMBER Level 3 Level 4 5 opportunities. Suggested grading: Level 6 7 opportunities. Suggested grading: count towards Level 4 if needed. Level 5 12 opportunities. Suggested grading: 4 = 5B, 7 = 5P, 10 = 5A. Work at Level 6 can count towards Level 5 if needed. 1a 25% 1c Rate of 125mB/day, so 3750 mB for a month 3 110.08, 110.309, 110.7, 111.3, 112.0 1b $225 ÷ 8 = 28.125 (i.e. 29 hours) 8 4b e.g. convert to 20 + 1d Answer is consistent with 1c but without clear reasoning for why it is the best solution. 1d Need some reasoning given e.g. 3 Gb is cheaper than 3 1gB packs. Similarly, need to use large data packs if possible. Buy a 3Gb pack and a 1Gb pack. While this is more data than needed, it is cheaper than buying a 3Gb, a 500 mB and 4 50 mB packs. Cost will be $70 per month. 1 = 4B, 3 = 4P, 5 = 4A. Work at Level 5 can 1b She needs to raise $225 4a e.g. 10% is 80, 20% is 160 4c e.g. 76 – 62 = 14 5 Nearest hundred column: any correct (4800, 5200, 100) 2a $681.85 15 20 = 23 20 3 or 1 20 5 2 d.p. column, at least 2 correct (4768.21, 5211.37, 59.01) 6a One percentage correctly calculated. e.g. 72% of $530 = $381.60 2b $734.30 4d e.g. 8 – 6 + 4 = 6 4e e.g. listing multiples, selects 24. 4f e.g. 5.2 × 4 × 108 = 2 080 000 000 5 3 s.f. column, at least 2 correct (4770, 5210, 59.0) 6a Correctly increases by 72% ($911.60) but does not add GST on top of this. 6b Consistent with 6a. Correct answer is $733.84 to the nearest cent. 6d $756.52 NCEA STYLE QUESTION Correctly calculates discounted cost of iPad or amount Tina earns per week. MHJC Page 57 2014 EOY Year 10 (104) 2 = 6B, 4 = 6P, 6 = 6A. 2c $977.50 6a $1048.34 6c 911.60−733.84 ×100 = 19.5% (1 d.p.) 911.60 NCEA STYLE QUESTION (fully solved gives 2 x evidence for L6. One mistake = 1 x evidence for L6) $ earned per week: 430 × 2 × 0.05 = $43 Discounted cost of iPad: 724 × 0.85 = $615.40 Amount Tina needs to save: 5/7 of 615.40 = $439.57 Time taken for Tina to save: 439.57/43 = 10.22 weeks – therefore 11 weeks, as 10 will not be enough. Section 2: ALGEBRA Level 3 Level 4 15 opportunities. Suggested grading: 4 = 4B, 8 = 4P, 12 = 4A. Work at Level 5 can Level 5 11 opportunities. Suggested grading: 3 = 5B, 6 = 5P, 9 = 5A. Work at Level 6 can count towards Level 5 if needed. Level 6 9 opportunities. Suggested grading: 2d 4 2f 4 or -3 (need both) 2e 10 3f 1a 5 count towards Level 4 if needed. 1b 4 diamonds 2a 18 2c 12 2b 12 3a p4 3e 9n 3b 3n 3c 2n + 5p 3g partially simplified 5a 5b + 5c 3d 56n2 4aiii 55 4ai b = number of biscuits, n = number of people 4bii 9.375% 4aii 70 5d 6n – n2 + 2n + 6 = -n2 + 8n + 6 4bi $3600 5i 6(7n – 2) 5b 12n + 48 5c 5p2 + p 6b (Writes and solves equation). If t = time in weeks, 15t + 100 = 520, t = 28 weeks 5d Either bracket set correctly expanded 6c solved, some working shown. 5e Either bracket set correctly expanded 6d solved for x, some working MHJC 8 3 = 6B, 5 = 6P, 7 = 6A. 11y 15 3 3g 2n5 5e 4y + 12 – 3y + 3 = y + 15 5f x2 + 2x – 8 5g p2 – 12p + 36 + 6p = p2 – 6p + 36 5j (x – 4)(x – 2) 6c (Must have a correct equation as well as solution) If j = James’ age (j + 2)(j – 1) = 154 j2 + j – 2 = 154 j2 – j – 156 = 0 (j + 13)(j – 12) = 0 As James’ age can’t be negative, James is 12. 5h 5(p + 2) 6d 5x – 20 = 180 6a 12x = 180, x = 15 (accept correct answer only) x = 40o Page 58 y = 180 – (2x40 + 38) = 62o 2014 EOY Year 10 (104) Both answers with working. 6b Correct answer without equation formed. MHJC Page 59 2014 EOY Year 10 (104) Section 3: GRAPHS Level 3 Level 4 6 opportunities. Suggested grading: 2 = 4B, 4 = 4P, 6 = 4A. Work at Level 5 can count towards Level 4 if needed. 2a 22, 26 1 Correctly plotted, may have one or two errors. 2b 75, 90 3a Pattern (P) 1 2 3 4 5 Matches (M) 4 7 10 13 16 Level 5 12 opportunities. Suggested grading: 5 = 5B, 8 = 5P, 10 = 5A. Work at Level 6 can count towards Level 5 if needed. 2d 34, 46 Level 6 8 opportunities. Suggested grading: 2e 5n – 8, 6n – 11 4c S = P2 + 3P + 2 (or equivalent) 3b M = 3P + 1 6b Draws inverted parabola with y intercept of -2 3c 70 4b (complete) Pattern (P) 1 2 3 4 5 4b (first two correct) 7b 4 km/h Squares (S) 6 12 20 30 42 5b -1/3 6a Redraws parabola 3 units higher 7a (3 pieces of evidence) Petra: y = -4x + 12 Anna: y = 2x Kelly: y = 6 5a 2 5c 0 7c Kelly’s house is 6km from Anna’s MHJC Page 60 3d Pattern 81 6c y = (x-1)2 or equivalent 3e 1 or (0, 1) 2c -1, -4 4a Gain at least 5P plus 2 = 6B, 4 = 6P, 6 = 6A. 2014 EOY Year 10 (104) 7c 6 km – shown by the y intercept of 6 and because we know Kelly is at home. 7d 2 km/h 7e At 4pm they are the same distance as each other from Anna’s house, but not necessarily in the same direction. Section 4: MEASUREMENT Level 3 Level 4 10 opportunities. Suggested grading: count towards Level 4 if needed. Level 5 8 opportunities. Suggested grading: 2 = 5B, 4 = 5P, 6 = 5A. Work at Level 6 can count towards Level 5 if needed. 5a 0.49 m 2b 2271 cm3 (nearest whole) 5b 1020 g 4a 10500 (rectangle section) + 3848 (two semicircles) = 14348 cm2 (nearest whole) 3 = 4B, 6 = 4P, 9 = 4A. Work at Level 5 can 1a 6000 cm2 (or equivalent) 2a 288 cm3 3 First thermometer 60o (+/- 2) 3 Second thermometer 42o (+/- 1) 5c 15.4 cm 5d 0.024 L 1b 0.6 × 500g = 300 g 4b 14348 × 22 = 315 656 cm3 (nearest whole. Mark for consistency with 4a). 6a 47 cm 6b 90 g 6c 190 cm 6d 625 cm 2 7a 8330 mm Level 6 7 opportunities. Suggested grading: At least 5P, plus… 1 = 6B, 3 = 6P, 5 = 6A. 4c 14348 × 28 = 401 744 cm3 = 401.744 L Time taken at 0.8 L/second: approximately 502 seconds (about 8 and a half minutes). 7c Vinyl: 2.345m × $90 + $120 = $331.05 Laminate: 2.002 × $180 = $360.36 7b e.g. 1000 × 2345 + 70 × 1700 - (1100 × 420) = 2002 000 mm2 (or 20020 cm2 or 2.002 m2 ) Therefore vinyl is cheaper. 8a 11π(52 - 22 ) = 725.7 cm3 9bi 13 × 9.22 × 16.1 = 454.2 cm3 9ai 48 cm2 9bii Cube root of previous answer (7.7 cm to nearest 1 d.p.) for length, width, height. 9aii 48 × 2.5 = 120 cm3 (mark for consistency with 9ai) 8b 200 × 12 × 11 = 26 400 cm2 9ci 179.6 cm3 (1 d.p.) 9cii 6177.6 cm3 of bath bomb mix. This will make 34 whole bath bombs. MHJC Page 61 2014 EOY Year 10 (104) MHJC Page 62 2014 EOY Year 10 (104) Section 5: TRIGONOMETRY Level 3 Students working at Level 3 are not expected to be able to access Trigonometry questions. Level 4 6 opportunities. Suggested grading: 2 = 4B, 4 = 4P, 6 = 4A. Work at Level 5 can count towards Level 4 if needed. 1a n2 = 65, n = 8.06 (2 d.p.) 2 1b n = 80, n = 8.94 (2 d.p.) 1c 4.59 (2 d.p.) Level 5 10 opportunities. Suggested grading: 3 = 5B, 5 = 5P, 7 = 5A Accept alternative rounding 2 2 3a √18 − 10 = 14.97 km (2 d.p.) 10 ) = 56.3o (1 d.p.) 3b cos−1 ( 18 4 (Two pieces of evidence) 1d 0.07 (2 d.p.) 35 x y 35 o 1e 29.7 (1 d.p.) = cos 72, x = 113.3 m = tan 72, y = 107.7 m 5 √32 − 0.92 = 2.86 m (2 d.p.) 2 2 2 6a x = √22 − 8 = 2 0.49 m (2 d.p.) 8 6b A = sin−1 ( 22 ) = 21.3o (1 d.p.) 6c 12 y = cos 50, y = 18.7 m (1 d.p.) 1.6 7a AB = sin 48, AB = 2.15 m (2 d.p.) 7b (Calculates AC) 1.6 e.g. AC = tan 48, AC = 1.44 m (2 d.p.) (Accept consistent Pythagoras working that Completes diagram (units not required) and/or uses an incorrectly calculated length AB.) gives solution x = √39 = 6.24 (2 d.p.) Level 6 4 opportunities. Suggested grading: At least 5P, plus 1 = 6B, 2 = 6P, 3 = 6A. 3c Third angle in triangle is 33.7o. This angle is supplementary to the bearing. 180 – 33.7 = 143.6 Bearing of 144 to nearest whole degree. 7b First calculates AC (see Level 5 column). CD = 4.2 – 1.44 = 2.76 m 1.6 BDC = tan−1 ( 2.76 ) = 30.1o (1 d.p.) 8 ½ bh = area 0.5 × 2.39 × BD = 1.61 BD = 1.35 (2 d.p.) 1.35 sin 20 = AB, AB = 3.95 m (1 d.p.) (Calculating AB is evidence of L6 alone) Therefore BC = 8.2 – 2.39 – 3.95 = 1.86 m 9 Horizontal distance from boat to plane = √122 + 322 = 3 4.18 km (2 d.p.) Height of plane = tan 29 × 34.18 = 18.94 km (2 d.p.) (Need height of plane for L6 evidence). MHJC Page 63 2014 EOY Year 10 (104) MHJC Page 64 2014 EOY Year 10 (104) Section 6: GEOMETRY Level 3 1a Octomino, one line of symmetry Level 4 10 opportunities. Suggested grading: 3 = 4B, 6 = 4P, 9 = 4A. Work at Level 5 can count towards Level 4 if needed. Level 5 8 opportunities. Suggested grading: 1ci (see below) 1cii (see below) 1ciii 2d Thessaloniki 2a Circle centred at Irakleions, radius 200, shaded inside. 3 = 5B, 5 = 5P, 7 = 5A 1b Octomino, two lines of symmetry Level 6 3 opportunities. Suggested grading: At least 5P plus 1 = 6B, 2 = 6P, 3 = 6A. 6 Identifies the danger zones AND indicates clearly where there are double dangers (overlapping loci, shaded below). Compass marks must be shown. 8a 4 8b Octomino with rotational symmetry drawn, 2e Canakkale 3 (Up to three pieces of evidence) A could be square, rectangle B could be rhombus, parallelogram C could be kite D could be trapezium 2b Perpendicular bisector construction 2c Angle Bisector construction. 5 4a 5 (Both) 4b MHJC Page 65 2014 EOY Year 10 (104) 9 One piece of evidence if 3 well-described steps. Two pieces if fully described. 8b Octomino with rotational symmetry drawn AND order of rotational symmetry stated. 6 A loci from this diagram can contribute ONE piece of evidence if not already gained from Question 2. 7 Valid triangular prism net. 9 Detailed description for one step, well-labelled = one piece of evidence. e.g. Reflect original in mirror m (1) Rotate original 90 degrees about point P (2) Reflect 2 in mirror n (3) Rotate 3 270 degrees about R (4) Enlarge 4 by scale factor 2 centre Q AND then translate 3 squares right and 2 up. Section 7: ANGLES Level 3 Level 4 8 opportunities. Suggested grading: 3 = 4B, 5 = 4P, 7 = 4A. 1a Puts a cross inside any angle other than ACB or the right angle. o 1b 90 MHJC Work at Level 5 can count towards Level 4 if needed. 1c CBA 1e 360o 2b 155o Level 5 13 opportunities. Suggested grading: 3 = 5B, 7 = 5P, 11 = 5A. Work at Level 6 can count towards Level 5 if needed. Level 6 5 opportunities. Suggested grading: 3a A = 135o (exterior angle of triangle = sum of other interior angles or angles on a straight line add to 180 o) 4 Full working leading to calculation of angle E, giving geometric reasons for each step (see Level 5 for an example) 3b A = 38o (co-interior angles on parallel lines add to 180 o) B = 142o (vertically opposite angles are equal) Page 66 2014 EOY Year 10 (104) 2 = 6B, 3 = 6P, 4 = 6A. 1d Puts a tick inside ACB 2a 65o (+/- 2) 2c 40o 2d 115o 3a A = 135o 3b A = 38o B = 142o 4 Accept angles with reasons for up to 4 pieces of evidence towards Level 5 e.g. a = 46o (angles on a straight line add to 180o) b = 46o (base angles of isosceles triangle are equal) c = 88o (angle sum of triangle is 180o) d = 46o (co-interior angles on parallel lines add to 180o) E = 46o (angles on a straight line add to 180o) OR because b and E are corresponding angles on parallel lines. on parallel lines add to 180o) r = 95o (angle sum of triangle) 5 Accept angles with reasons for up to 3 pieces of evidence towards Level 5 e.g. p = 40o (angles on a straight line add to 180o) q = 45o (co-interior angles A = 85o (angles on a straight line) 6 One angle calculated with geometric reason. 7 Any angles calculated with geometric reasons (allow up to 4 pieces of evidence towards Level 5). See Level 6 column for reasoning example. MHJC Page 67 2014 EOY Year 10 (104) 5 Full working leading to calculation of angle A, giving geometric reasons for each step. (see Level 5 for an example) 6 Completed proof. Angles ABC and ADE are equal because: they are corresponding angles on parallel lines Angles ACB and AED are equal because: they are corresponding angles on parallel lines Angles BAC is also Angle DAE Because triangles ABC and ADE have all angles the same, they are similar triangles. 7 a = 22o (base angles of isosceles triangle are equal) b = 1 36o (angle sum of triangle) c = 3 1o (base angles of isosceles triangle are equal) d = 1 18o (angle sum of triangle) e = 1 06o (angles about a point) Conclusion: Angle ACB = 31 + 22 = 53. Angle e is double angle ACB (must have conclusion) 8 Angle all found in terms of x (see below) MHJC Page 68 2014 EOY Year 10 (104) Section 8: STATISTICS Level 3 Level 4 6 opportunities. Suggested grading: 2 = 4B, 4 = 4P, 6 = 4A. 2a Continuous 3a Work at Level 5 can count towards Level 4 if needed. 1a General description e.g. that the percentage is generally falling over time. 1b A scatterplot 1e Estimate in the range 15-25%. 3b Calculates mode or range 2d No – it does not look like half the data is below 50. 3b Calculates median or mean 4a Cars travelling faster past Sam tended to be travelling faster past Katrina (or other valid description of correlation). Level 5 8 opportunities. Suggested grading: 2 = 5B, 4 = 5P, 6 = 5A. Work at Level 6 can count towards Level 5 if needed. Level 6 5 opportunities. Suggested grading: 1a More detailed description e.g. that in 1996 it was over 80%, gradually dropping, then dropped quickly between 2001-2005, slowing again after that and finishing with a short rise. 1c ONE OF reason for sampling, suggested collection method e.g. It is not realistic to have found the speed of every single car. 1d We only have percentages. We need to know how many cars are on the road to calculate numbers that were speeding. 2b There are gaps between bars – usually a histogram would be used. Nearest 1 km/h. 2c Up to 2 pieces of evidence for comments on at least 2 features e.g. peaks around 60, slightly asymmetrical, a few outlier values in both tails, range of about 50. 3b Calculates median and quartiles (other statistics given below). Range 11 Median 53 Mean 51.16 Mode 53 Lower quartile 50.5 Upper quartile 55.5 3c or consistent with table. 1c Reason for sampling AND suggested collection method e.g. It is not realistic to find the speed of every single car. Data could be gathered from speed cameras and police scans on car speeds. 2c One piece of evidence if 3 features are commented on clearly. 3d At least two comments e.g. Sam is only there at one time of day (not representative of other times). Cars may tend to travel more slowly at certain times e.g. at 3pm when a lot of students are crossing. Sam’s visible presence may change the behaviours of drivers. 4c Answer with justification e.g. yes, Katrina is correct. If I draw a line to show y = x, most of the points fall beneath it (or most points have a smaller x value than y value). 5 (gives at least 2 comments, e.g.) ● Biased sample ● Not all may have cars ● Not all may drive past the school ● Q3 makes the assumption that they break the limit – they may not. ● Q2 people may be unwilling to admit they break the limit 4b Reasonable position for line of best fit. MHJC Page 69 2014 EOY Year 10 (104) At least 5P, plus 2 = 6B, 3 = 6P, 4 = 6A. ● MHJC Page 70 2014 EOY Year 10 (104) Q1 people may not be able to answer accurately. Section 9: PROBABILITY Level 3 1a Impossible Level 4 6 opportunities. Suggested grading: 2 = 4B, 4 = 4P, 6 = 4A. Work at Level 5 can count towards Level 4 if needed. 1c Placed over ½ 2a Black/Black, Black/Brown, Black/Silver, Brown/Black, Brown/Brown, Brown/Silver, Silver/Black, Silver/Brown, Silver/Silver. 1d Place under ½ 2b ¼ 1b ½ 28 4a 50 = 14 25 4bi e.g. 6248 10 000 5a Level 5 5 opportunities. Suggested grading: 2 = 4B, 4 = 4P, 5 = 4A. Work at Level 6 can count towards Level 5 if needed. 3a Level 6 8 opportunities. Suggested grading: 2 = 6B, 4 = 6P, 6 = 6A. 1 1 2c 2 × 2 + 1 1 3×3 + 1 1 6×6 = 14 36 or 187 2d e.g. calculates 2c and comments that it is below 50%, therefore different colours are more likely. 3c 0.5 × 0.88 + 0.5 × 0.91 = 0.895 = 781 1250 or equivalent 1 3 3b 0.5 × 0.09 = 0.045 4bii No – because (e.g.) every time you run a probability experiment, the results can be different. Each set of trials just gives one estimate. 5b 12 5c ½ 1 5d (½)5 = 32 or equivalent (e.g. 0.03125) 3d (0.5 × 0.12)3 = 0.000216 3e 700 × 0.105 = 73.5 (accept 73 or 74) 3f Answers will vary e.g. assume the school has equal numbers of males and females. 4c The 10 000 trials will give a better estimate, as long-run experiments give more reliable results than smaller numbers of trials. 5e Probability of one of these two words is 1 . From 100 trials, we would expect to get 6 them 16 or 17 times. (Based on this, either say it is more than what we would expect or not too far off to be truly unusual). MHJC Page 71 2014 EOY Year 10 (104) MHJC Page 72 2014 EOY Year 10 (104)