Math 7 · Unit 16: Interpreting and discussing results · Cambridge Lower Secondary Maths Stage 7

Questions

1. 1. A group of students are timed as they complete a task. Their times, in seconds, are shown. Work out the mode, median and mean time.

   • mode 20 s, median 18 s, mean 17.4 s
   • mode 20 s, median 15 s, mean 19 s
   • mode 14 s, median 18 s, mean 20 s
   • mode 20 s, median 18 s, mean 19 s
   Check

2. 2. Marcus, Arun and Zara discuss which average best represents the data. Marcus: I would use the mode because it is the most popular. Arun: I would use the mean because the calculation uses all the values. Zara: I wouldn't use the mode because only two of the times are greater than the mode. I wouldn't use the mean because there is one really large value that will make the mean too large. I would use the median because it is nicely in the middle of the data. Who do you think is correct?

   • None of them
   • Arun
   • Marcus
   • Zara
   Check

3. 3. Students in a science class take a test. Here are their marks. Work out the mode, median and mean.

   • mode 44, median 39, mean 38.4
   • mode 32 and 44 (bimodal), median 40, mean 38.4
   • mode 32, median 40, mean 38
   • no mode, median 40, mean 38.4
   Check

4. 4. Which average best represents the data? Give a reason for your choice of average.

   • The mode, because it is the most common mark
   • The range, because it shows how spread out the marks are
   • None of them, because there are two modes
   • The mean, because it uses all the marks and there are no extreme values
   Check

5. 5. These are the numbers of goals scored in 20 football matches played in January. Put the different numbers of goals scored in order of size, starting with the smallest.

   Put these in order.

   • 4
   • 0
   • 5
   • 3
   • 1
   • 6
   • 2
   Check

6. 6. These are the numbers of goals scored in 20 football matches in January. Find the mode, median and mean number of goals.

   • mode 4, median 3, mean 2.6
   • mode 0, median 3, mean 2.6
   • mode 4, median 2.5, mean 3
   • mode 4, median 3, mean 2.2
   Check

7. 7. Which average best represents the data? Give a reason for your choice of average.

   • The range, because it uses the largest and smallest numbers
   • None of them, because the numbers go from 0 to 6
   • The mean, because it uses every match's goals
   • The mode, because it is the most common number of goals
   Check

8. 8. These are the numbers of goals scored in 20 football matches in January. Work out the range. In February the range is 4. In which month is there more variation?

   • range 4; they are the same
   • range 6; January has more variation
   • range 5; January has more variation
   • range 6; February has more variation
   Check

9. 9. This table shows the numbers of cars owned by 20 different families living in the same street. Write down the modal and median number of cars.

   • mode 1, median 1
   • mode 0, median 1
   • mode 8, median 2
   • mode 1, median 2
   Check

10. 10. Copy and complete the working to find the mean number of cars per family.

    Fill the blanks with these.

    • 6
    • 5.2
    • 4
    • 1.3
    • 20
    • 8
    • 1.5
    • 26
    Check

11. 11. Which average best represents the data? Give a reason for your choice of average.

    • The range, because it uses the largest and smallest numbers
    • The mean, because 1.3 cars is a number of cars that no family has
    • None of them, because the numbers go from 0 to 4
    • The median, because it is the middle number of cars and a few large families do not pull it up
    Check

12. 12. Work out the range in the number of cars owned.

    • 4
    • 5
    • 8
    • 1
    Check

13. 13. A different group of families has a range of two cars. Which group of families, the first or the second, has more variation in the number of cars owned?

    • the first group
    • the second group
    • They are the same.
    Check

14. 14. These are the ages of 50 children at a small school. Work out the mode, median and mean age.

    • mode 6, median 8, mean 8.5
    • mode 6, median 8.5, mean 8.04
    • mode 6, median 8, mean 8.04
    • mode 12, median 8.5, mean 8.5
    Check

15. 15. Which average best represents the data? Give a reason for your choice of average.

    • None of them, because the ages go from 6 to 11
    • The mean, because it uses every age and there are no extreme values
    • The range, because it uses the youngest and oldest ages
    • The mode, because it is the most common age
    Check

16. 16. These are the ages of 50 children at a small school. Work out the range. A different school has a range of seven years. Which school has more variation?

    • range 5; the first school
    • range 11; the first school
    • range 6; the first school
    • range 5; the second school
    Check

17. 17. Some children in a swimming club recorded how many lengths they could swim without stopping. Work out the mode, median and mean number of lengths.

    • mode 4, median 3, mean 2.29
    • mode 10, median 2, mean 2
    • mode 0, median 3, mean 2.5
    • mode 4, median 2, mean 2.5
    Check

18. 18. Which average best represents the data? Give a reason for your choice of average.

    • The mode, because it is the most popular
    • None of them, because the numbers go from 0 to 4
    • The median, because the mode is at one end of the data and the median is in the middle
    • The range, because it uses the largest and smallest numbers
    Check

19. 19. Work out the range in the number of lengths the children could swim.

    • 10
    • 5
    • 28
    • 4
    Check

20. 20. The range is 4 lengths. A different club has a range of eight lengths. Which club, the first or the second, has less variation in the number of lengths the children could swim?

    • the first club
    • the second club
    • They are the same.
    Check