Practice questions
Original questions written by HomiLabs in the style of the exam, with answers and mark schemes. They are not
Cambridge past paper questions and have not been reviewed by Cambridge. Try each one before opening the answer.
Q1Averages & range · Core · Paper 1 style · no calculator · 5 marksThe ages, in years, of 9 children at a cricket academy in Sialkot are:12, 15, 11, 14, 12, 13, 16, 12, 12
- (a) Write down the mode. [1]
- (b) Find the median. [1]
- (c) Find the range. [1]
- (d) Calculate the mean. [2]
Show answer
- (a) 12
B1
- (b) 12
Ordered: 11, 12, 12, 12, 12, 13, 14, 15, 16; middle (5th) value. B1
- (c) 5
16 − 11 = 5. B1
- (d) 13
Total = 117 M1; 117 ÷ 9 = 13 A1
Q2Averages & range · Core · Paper 3 style · calculator · 5 marksThe rainfall, in mm, recorded in Lahore on 10 days in July was:0, 12.4, 3.6, 0, 25.0, 8.2, 0, 15.8, 4.4, 6.6
- (a) Calculate the mean daily rainfall. [2]
- (b) Find the median daily rainfall. [2]
- (c) Find the range. [1]
Show answer
- (a) 7.6 mm
Total = 76.0 M1; 76.0 ÷ 10 = 7.6 A1
- (b) 5.5 mm
Ordered: 0, 0, 0, 3.6, 4.4, 6.6, 8.2, 12.4, 15.8, 25.0 M1; (4.4 + 6.6) ÷ 2 = 5.5 A1
- (c) 25 mm
25.0 − 0 = 25. B1
Q3Averages & range · Core · Paper 3 style · calculator · 4 marksAt a motorway toll plaza, the number of people in each of 60 cars was counted.Number of people: 1, 2, 3, 4, 5Frequency: 23, 17, 9, 7, 4
- (a) Write down the mode. [1]
- (b) Find the median. [1]
- (c) Calculate the mean number of people per car. [2]
Show answer
- (a) 1
B1
- (b) 2
30th and 31st values: cumulative 23, 40, so both are 2. B1
- (c) 2.2
Σfx = 23 + 34 + 27 + 28 + 20 = 132 M1; 132 ÷ 60 = 2.2 A1
Q4Averages & range · Standard · Paper 2 style · no calculator · 3 marksA teacher asked her class how many books they read last month.Number of books: 0, 1, 2, 3Frequency: 3, x, 6, 4The mean number of books is 1.55.
- (a) Show that 0.55x = 3.85. [2]
- (b) Find x. [1]
Show answer
- (a) (x + 24) ÷ (x + 13) = 1.55 gives x + 24 = 1.55x + 20.15, so 0.55x = 3.85
Σfx = x + 12 + 12 = x + 24 and Σf = x + 13 M1; equation and rearrangement A1
- (b) x = 7
3.85 ÷ 0.55 = 7 B1
Q5Averages & range · Standard · Paper 2 style · no calculator · 5 marksThe mean of five numbers is 8. Four of the numbers are 3, 7, 9 and 12.
- (a) Find the fifth number. [2]
- (b) A sixth number is added. The mean of the six numbers is now 9. Find the sixth number. [2]
- (c) Find the range of the six numbers. [1]
Show answer
- (a) 9
5 × 8 = 40 M1; 40 − (3 + 7 + 9 + 12) = 9 A1
- (b) 14
6 × 9 = 54 M1; 54 − 40 = 14 A1
- (c) 11
14 − 3 = 11 B1
Q6Averages & range · Standard · Paper 4 style · calculator · 6 marksThe table shows the time, t minutes, that 60 commuters in Karachi took to travel to work.0 < t ≤ 10: 810 < t ≤ 20: 1520 < t ≤ 30: 2230 < t ≤ 40: 1040 < t ≤ 60: 5
- (a) Calculate an estimate of the mean time. [4]
- (b) Write down the modal class. [1]
- (c) Write down the class that contains the median. [1]
Show answer
- (a) 23.6 minutes (23.58…)
Mid-values 5, 15, 25, 35, 50 M1; Σfx = 40 + 225 + 550 + 350 + 250 = 1415 M1; ÷ 60 M1; 23.6 A1
- (b) 20 < t ≤ 30
B1
- (c) 20 < t ≤ 30
30th/31st values; cumulative 8, 23, 45 B1
Q7Averages & range · Standard · Paper 4 style · calculator · 4 marksA biology student measured the heights, in cm, of 11 bean seedlings:4.2, 5.8, 3.9, 6.1, 5.0, 4.7, 7.3, 5.5, 4.4, 6.6, 5.2
- (a) Find the median. [1]
- (b) Find the lower quartile and the upper quartile. [2]
- (c) Find the interquartile range. [1]
Show answer
- (a) 5.2 cm
Ordered: 3.9, 4.2, 4.4, 4.7, 5.0, 5.2, 5.5, 5.8, 6.1, 6.6, 7.3; 6th value B1
- (b) LQ = 4.4 cm, UQ = 6.1 cm
3rd value and 9th value B1 B1
- (c) 1.7 cm
6.1 − 4.4 = 1.7 B1
Q8Averages & range · Standard · Paper 1 style · no calculator · 4 marksThe prices, in lakh rupees, of 7 houses sold in one street last year were:80, 95, 85, 90, 450, 88, 92
- (a) Find the median price. [1]
- (b) Find the mean price. [2]
- (c) Explain why the median is a better average than the mean for these prices. [1]
Show answer
- (a) 90 lakh rupees
Ordered: 80, 85, 88, 90, 92, 95, 450 B1
- (b) 140 lakh rupees
Total 980 M1; 980 ÷ 7 = 140 A1
- (c) The 450 lakh house is an extreme value that makes the mean larger than six of the seven prices; the median is not affected by it.
B1 for reference to the extreme value / outlier
Q9Averages & range · Challenge · Paper 4 style · calculator · 4 marksClass A has 18 students and their mean mark in a test is 64.Class B has 22 students and their mean mark in the same test is 59.
- (a) Calculate the mean mark of all 40 students. [2]
- (b) Later it was found that one student in Class B scored 85, but the mark was recorded as 58. Calculate the correct mean mark of all 40 students. [2]
Show answer
- (a) 61.25
18 × 64 + 22 × 59 = 1152 + 1298 = 2450 M1; 2450 ÷ 40 = 61.25 A1
- (b) 61.925 (61.9 to 3 s.f.)
Total increases by 27 M1; 2477 ÷ 40 = 61.925 A1
Q10Averages & range · Challenge · Paper 2 style · no calculator · 4 marksFour positive integers have a mode of 6, a median of 7 and a mean of 8.
- (a) Find the four integers. [3]
- (b) Find the range of the four integers. [1]
Show answer
- (a) 6, 6, 8, 12
Mode 6 so at least two 6s; median 7 means the middle two add to 14, so the two smallest are 6 and 6 and the third is 8 M1; total = 4 × 8 = 32 M1; fourth = 32 − 20 = 12 A1
- (b) 6
12 − 6 = 6 B1
Q11Averages & range · Challenge · Paper 2 style · no calculator · 5 marksThe mean of a list of n numbers is 12.
- (a) The number 30 is added to the list and the mean becomes 13. Find n. [3]
- (b) Two numbers, both equal to k, are then removed from the new list. The mean of the numbers left is 12. Find k. [2]
Show answer
- (a) n = 17
12n + 30 = 13(n + 1) M1 M1; n = 17 A1
- (b) k = 21
Total 13 × 18 = 234 and 16 × 12 = 192 M1; 2k = 42, k = 21 A1
Q12Charts, tables & diagrams · Core · Paper 1 style · no calculator · 3 marks72 students were asked to choose their favourite sport.Cricket 30, Football 18, Hockey 12, Badminton 12
- (a) Calculate the sector angle for each sport in a pie chart. [3]
Show answer
- (a) Cricket 150°, Football 90°, Hockey 60°, Badminton 60°
360 ÷ 72 = 5° per student M1; 30 × 5, 18 × 5, 12 × 5 A2 (A1 for two correct)
Q13Charts, tables & diagrams · Core · Paper 3 style · calculator · 5 marksThe masses, in kg, of 15 parcels at a courier office are:23, 31, 18, 27, 35, 42, 29, 31, 24, 19, 38, 31, 26, 40, 33
- (a) Draw an ordered stem-and-leaf diagram for these masses. Include a key. [3]
- (b) Find the median. [1]
- (c) Find the range. [1]
Show answer
- (a) 1 | 8 92 | 3 4 6 7 93 | 1 1 1 3 5 84 | 0 2Key: 2 | 3 means 23 kg
B2 for correct ordered leaves (B1 unordered or one error); B1 key
- (b) 31 kg
8th value B1
- (c) 24 kg
42 − 18 B1
Q14Charts, tables & diagrams · Core · Paper 1 style · no calculator · 3 marksA pictogram shows the number of cups of chai sold at a school canteen. One symbol represents 8 cups.Monday: 3½ symbolsTuesday: 2¼ symbols
- (a) How many cups were sold on Monday? [1]
- (b) How many cups were sold on Tuesday? [1]
- (c) On Wednesday 22 cups were sold. How many symbols should be drawn for Wednesday? [1]
Show answer
- (a) 28
3.5 × 8 B1
- (b) 18
2.25 × 8 B1
- (c) 2¾ symbols
22 ÷ 8 = 2.75 B1
Q15Charts, tables & diagrams · Standard · Paper 1 style · no calculator · 4 marksA pie chart shows the main cooking fuel used by 240 households in a village.
- (a) The sector for LPG has an angle of 66°. How many households use LPG? [2]
- (b) 30 households use wood. Calculate the sector angle for wood. [2]
Show answer
- (a) 44
66 ÷ 360 × 240 M1; 44 A1
- (b) 45°
30 ÷ 240 × 360 M1; 45 A1
Q16Charts, tables & diagrams · Standard · Paper 3 style · calculator · 5 marksThe two-way table shows how 120 students travel to school.Bus: boys 24, girls ?, total 45Car: boys ?, girls 18, total 31Walk: boys ?, girls 21, total ?Total: boys 60, girls ?, total 120
- (a) Complete the table. [3]
- (b) What percentage of the students walk to school? Give your answer correct to 1 decimal place. [2]
Show answer
- (a) Bus: girls 21. Car: boys 13. Walk: boys 23, total 44. Totals: girls 60.
Girls total 120 − 60 = 60; bus girls 45 − 24 = 21; car boys 31 − 18 = 13; walk boys 60 − 24 − 13 = 23; walk total 23 + 21 = 44. B3 (B2 for 3 or 4 correct, B1 for 2)
- (b) 36.7%
44 ÷ 120 × 100 M1; 36.7 A1
Q17Charts, tables & diagrams · Standard · Paper 3 style · calculator · 6 marksTwo groups of athletes ran 100 m. Their times, in seconds, are shown as stem-and-leaf diagrams.Group A: 12 | 8 13 | 2 7 9 14 | 1 4 15 | 0Group B: 12 | 5 9 13 | 0 4 14 | 7 15 | 8 16 | 2Key: 13 | 2 means 13.2 seconds
- (a) Find the median time for each group. [2]
- (b) Find the range for each group. [2]
- (c) Make two comparisons between the times of the two groups. [2]
Show answer
- (a) Group A 13.9 s, Group B 13.4 s
4th value of each ordered list B1 B1
- (b) Group A 2.2 s, Group B 3.7 s
15.0 − 12.8 and 16.2 − 12.5 B1 B1
- (c) Group B was faster on average (lower median); Group A's times were more consistent (smaller range).
B1 each; must refer to the average and to the spread in context
Q18Charts, tables & diagrams · Challenge · Paper 2 style · no calculator · 4 marksIn a pie chart showing people's favourite colours, the sector angles are:red 3x°, blue (2x + 10)°, green 90°, yellow (x + 20)°.
- (a) Find x. [2]
- (b) 18 people chose yellow. How many people were asked altogether? [2]
Show answer
- (a) x = 40
3x + 2x + 10 + 90 + x + 20 = 360 M1; 6x = 240, x = 40 A1
- (b) 108
Yellow angle = 60° M1; 18 × 360 ÷ 60 = 108 A1
Q19Charts, tables & diagrams · Challenge · Paper 4 style · calculator · 4 marksTwo pie charts show what happened to a town's waste.In 2020 the town produced 480 tonnes of waste and the sector for 'recycled' was 75°.In 2025 the town produced 600 tonnes of waste and the sector for 'recycled' was 96°.
- (a) Find the mass of waste recycled in each year. [2]
- (b) Calculate the percentage increase in the mass recycled from 2020 to 2025. [2]
Show answer
- (a) 2020: 100 tonnes; 2025: 160 tonnes
75 ÷ 360 × 480 B1; 96 ÷ 360 × 600 B1
- (b) 60%
(160 − 100) ÷ 100 × 100 M1; 60 A1
Q20Cumulative frequency & box plots · Core · Paper 2 style · no calculator · 4 marksFifteen students recorded the number of text messages they sent in one day:12, 30, 7, 15, 21, 3, 18, 24, 10, 36, 8, 27, 15, 13, 20
- (a) Find the median. [1]
- (b) Find the lower quartile and the upper quartile. [2]
- (c) Write down the five values needed to draw a box plot. [1]
Show answer
- (a) 15
Ordered: 3, 7, 8, 10, 12, 13, 15, 15, 18, 20, 21, 24, 27, 30, 36; 8th value B1
- (b) LQ 10, UQ 24
4th and 12th values B1 B1
- (c) 3, 10, 15, 24, 36
minimum, LQ, median, UQ, maximum B1
Q21Cumulative frequency & box plots · Standard · Paper 4 style · calculator · 4 marksThe masses of 200 apples were recorded. The cumulative frequency curve passes through these points (mass in g, cumulative frequency):(100, 0), (120, 14), (130, 38), (134, 50), (140, 72), (148, 100), (155, 124), (160, 150), (170, 182), (180, 196), (190, 200)
- (a) Find the median mass. [1]
- (b) Find the interquartile range. [2]
- (c) Find the number of apples with a mass of more than 170 g. [1]
Show answer
- (a) 148 g
cf = 100 B1
- (b) 26 g
LQ at cf 50 = 134, UQ at cf 150 = 160 M1; 160 − 134 = 26 A1
- (c) 18
200 − 182 B1
Q22Cumulative frequency & box plots · Standard · Paper 2 style · no calculator · 4 marksBox plots show the journey times, in minutes, of students at two schools.School P: minimum 12, lower quartile 18, median 23, upper quartile 30, maximum 41School Q: minimum 10, lower quartile 21, median 25, upper quartile 28, maximum 35
- (a) Find the range and the interquartile range of the journey times for School P. [2]
- (b) Make two comparisons between the journey times for the two schools. [2]
Show answer
- (a) Range 29 min, IQR 12 min
41 − 12 B1; 30 − 18 B1
- (b) School Q had a higher median (25 > 23), so journeys were longer on average; School Q had a smaller IQR (7 < 12), so its times were more consistent.
B1 for median comparison, B1 for IQR (or range) comparison, in context
Q23Cumulative frequency & box plots · Challenge · Paper 4 style · calculator · 6 marksThe heights, h cm, of 80 plants are shown.0 < h ≤ 10: 610 < h ≤ 20: 1420 < h ≤ 30: 2830 < h ≤ 40: 2240 < h ≤ 60: 10
- (a) Write down the cumulative frequencies. [2]
- (b) Use linear interpolation within the class to estimate the median height. [2]
- (c) Estimate the number of plants taller than 35 cm. [2]
Show answer
- (a) 6, 20, 48, 70, 80
B2 (B1 for 3 correct)
- (b) 27.1 cm (27.14…)
40th value lies in 20 < h ≤ 30 M1; 20 + (40 − 20) ÷ 28 × 10 = 27.1 A1 (from a graph accept 26 to 28)
- (c) 21
Half of 22 = 11 M1; 11 + 10 = 21 A1
Q24Scatter diagrams · Core · Paper 1 style · no calculator · 3 marksWrite down the type of correlation you would expect between each pair of quantities.
- (a) the temperature on a summer day and the number of ice creams sold at a beach in Karachi [1]
- (b) the age of a car and its value [1]
- (c) a student's shoe size and their mark in a history test [1]
Show answer
- (a) Positive correlation
B1
- (b) Negative correlation
B1
- (c) No correlation
B1
Q25Scatter diagrams · Core · Paper 3 style · calculator · 6 marksThe table shows the number of hours, h, eight students revised and their test scores, s (out of 100).h: 2, 5, 1, 8, 4, 6, 3, 7s: 41, 58, 35, 75, 52, 63, 46, 70
- (a) Calculate the mean number of hours and the mean score. [2]
- (b) Describe the correlation. [1]
- (c) A line of best fit passes through the point of means and through (0, 28). Use the line to estimate the score of a student who revised for 5.5 hours. [2]
- (d) Explain why it would not be sensible to use the line to estimate the score of a student who revised for 15 hours. [1]
Show answer
- (a) 4.5 hours, 55
36 ÷ 8 B1; 440 ÷ 8 B1
- (b) Positive
B1
- (c) 61
gradient (55 − 28) ÷ 4.5 = 6 M1; 28 + 6 × 5.5 = 61 A1 (accept a reading from a graph of 59 to 63)
- (d) 15 hours is outside the range of the data (extrapolation); the line would give 118, more than the maximum mark.
B1
Q26Scatter diagrams · Standard · Paper 4 style · calculator · 5 marksOn the same afternoon, a geography group recorded the height above sea level, h metres, and the temperature, T °C, at seven places in northern Pakistan.h: 500, 1200, 2000, 2600, 3100, 3800, 4500T: 31, 27, 21, 18, 14, 10, 5
- (a) Describe the correlation and what it shows. [2]
- (b) The equation of the line of best fit is T = 34.4 − 0.0065h. Use it to estimate the temperature at a place 3400 m above sea level. [2]
- (c) Explain why the line should not be used to estimate the temperature at the summit of a mountain 8000 m high. [1]
Show answer
- (a) Strong negative correlation: the higher the place, the lower the temperature.
B1 strong negative, B1 interpretation
- (b) 12.3 °C
34.4 − 0.0065 × 3400 M1; 12.3 A1
- (c) 8000 m is far outside the range of the data, so the estimate is an extrapolation and unreliable.
B1
Q27Scatter diagrams · Challenge · Paper 2 style · no calculator · 5 marksThe table shows the engine size, in litres, and the fuel economy, in km per litre, of seven cars.Engine size: 1.0, 1.3, 1.6, 1.8, 2.0, 2.4, 3.0Fuel economy: 18, 16.5, 15, 9, 13, 11.5, 8
- (a) One car does not fit the trend. Write down its engine size. [1]
- (b) The line of best fit passes through (1.0, 18) and (3.0, 8). Find its gradient and explain what it means in this context. [3]
- (c) Use the line to estimate the fuel economy of a car with a 2.2-litre engine. [1]
Show answer
- (a) 1.8 litres
9 km/l is far below the other cars of similar engine size B1
- (b) Gradient −5: fuel economy falls by about 5 km per litre for each extra litre of engine size.
(8 − 18) ÷ (3.0 − 1.0) M1; −5 A1; interpretation B1
- (c) 12 km per litre
18 − 5 × 1.2 = 12 B1
Q28Histograms · Standard · Paper 4 style · calculator · 4 marksThe ages, a years, of 150 visitors to the Lahore Museum one morning are shown.0 < a ≤ 10: 2010 < a ≤ 25: 4525 < a ≤ 40: 3640 < a ≤ 60: 3460 < a ≤ 90: 15
- (a) Calculate the frequency density for each class, to draw a histogram. [3]
- (b) Which class has the tallest bar? [1]
Show answer
- (a) 2, 3, 2.4, 1.7, 0.5
frequency ÷ class width M1; 20 ÷ 10, 45 ÷ 15, 36 ÷ 15, 34 ÷ 20, 15 ÷ 30 A2 (A1 for 3 correct)
- (b) 10 < a ≤ 25
Highest frequency density, 3 B1
Q29Histograms · Standard · Paper 2 style · no calculator · 5 marksA histogram shows the time, t minutes, that students took to finish a puzzle. The heights of the bars (frequency densities) are:0 < t ≤ 5: 2.45 < t ≤ 10: 410 < t ≤ 20: 3.220 < t ≤ 40: 0.8
- (a) Find the frequency for each class and the total number of students. [3]
- (b) Estimate the number of students who took more than 15 minutes. [2]
Show answer
- (a) 12, 20, 32, 16; total 80
fd × width M1; 2.4 × 5, 4 × 5, 3.2 × 10, 0.8 × 20 A1; total 80 A1
- (b) 32
half of 32 = 16 M1; 16 + 16 = 32 A1
Q30Histograms · Challenge · Paper 4 style · calculator · 8 marksThe masses, m grams, of fish caught by a boat at Gwadar are summarised.0 < m ≤ 100: 12100 < m ≤ 150: ?150 < m ≤ 200: 30200 < m ≤ 300: ?300 < m ≤ 500: 8On the histogram, the bar for 0 < m ≤ 100 has frequency density 0.12, the bar for 100 < m ≤ 150 has frequency density 0.46 and the bar for 200 < m ≤ 300 has frequency density 0.21.
- (a) Find the two missing frequencies. [2]
- (b) Find the frequency densities for the classes 150 < m ≤ 200 and 300 < m ≤ 500. [2]
- (c) Calculate an estimate of the mean mass. Give your answer correct to 1 decimal place. [4]
Show answer
- (a) 100 < m ≤ 150: 23; 200 < m ≤ 300: 21
0.46 × 50 B1; 0.21 × 100 B1
- (b) 0.6 and 0.04
30 ÷ 50 B1; 8 ÷ 200 B1
- (c) 182.7 g
Mid-values 50, 125, 175, 250, 400 M1; Σfx = 17 175 M1; Σf = 94 M1; 182.7 A1