Math 9 · Unit 15: Interpreting and discussing results · Cambridge Lower Secondary Maths Stage 9

Questions

1. 1. The table shows the French and Spanish test results of 15 learners. Each test was marked out of 20. Which of these statements correctly describes the data on the scatter graph? A: The better learners do in the French test, the better they do in the Spanish test. Also, the worse learners do in the French test, the worse they do in the Spanish test. B: The better learners do in the French test, the worse they do in the Spanish test. Also, the worse learners do in the French test, the better they do in the Spanish test.

   • Both A and B
   • A
   • B
   • Neither A nor B
   Check

2. 2. The table shows the Art and Science test results of 15 learners. Each test was marked out of 20. Which statement describes the data on the scatter graph?

   • The better learners do in Art, the worse they do in Science.
   • The better learners do in Art, the better they do in Science.
   • There is no link between Art and Science.
   • Everyone did better in Science.
   Check

3. 3. Maha asks 15 learners how many hours a week they spend reading and what they scored in a spelling test (out of 20). What type of correlation does the scatter graph show?

   • strong positive correlation
   • no correlation
   • negative correlation
   • weak negative correlation
   Check

4. 4. Maha asks 15 learners how many hours a week they spend reading and what they scored in a spelling test (out of 20). Maha reads for 12 hours a week. Using a line of best fit, which is the best estimate of her spelling score?

   • about 12
   • about 16
   • about 20
   • about 8
   Check

5. 5. The graph shows the packets of biscuits and the packets of crisps sold by a grocery store each day over 10 days. What correlation does the scatter graph show?

   • no correlation
   • perfect correlation
   • strong positive correlation
   • strong negative correlation
   Check

6. 6. The table shows the maths and drama exam results of 15 learners. Without looking at the values, which correlation would you expect between the maths and drama results of the learners?

   • no correlation
   • perfect correlation
   • negative correlation
   • positive correlation
   Check

7. 7. The scatter graph shows the maths and drama exam results (%) of 15 learners. What type of correlation does it show?

   • no correlation
   • weak negative correlation
   • strong positive correlation
   • strong negative correlation
   Check

8. 8. A learner expected that learners who do well in maths do less well in drama. Does the scatter graph of maths and drama exam results show this was correct?

   • Yes
   • No
   Check

9. 9. The scatter graph shows the maths and drama exam results (%) of 15 learners. Use a line of best fit to estimate the drama exam result of a learner who scored 50% in their maths exam.

   • about 90%
   • about 30%
   • about 50%
   • about 70%
   Check

10. 10. The scatter graph shows the number of hats bought in one year by 12 adults and the length of their hair. Arun says: "The scatter graph shows negative correlation. This means that the longer your hair, the fewer hats you need." Marcus says: "That can't be true! Having short hair does not mean you need more hats than someone with long hair." Is Marcus correct?

    • Yes
    • No
    Check

11. 11. The scatter graph shows the algebra and geometry test results of 10 learners. Both tests were marked out of 20. What type of correlation does it show?

    • zero correlation
    • positive correlation
    • no correlation
    • negative correlation
    Check

12. 12. The scatter graph shows the algebra and geometry test results of 10 learners. Learners with a total score of more than 20 do not have to resit both tests. How many of the learners do have to resit both tests?

    • 6
    • 3
    • 4
    • 5
    Check

13. 13. The scatter graph shows the algebra and geometry test results of 10 learners. Both tests were marked out of 20. Work out the mean algebra score.

    • 9
    • 12
    • 10
    • 13
    Check

14. 14. The scatter graph shows the algebra and geometry test results of 10 learners. Both tests were marked out of 20. Work out the mean geometry score.

    • 14
    • 12
    • 13
    • 10
    Check

15. 15. The algebra and geometry results of 10 learners have a mean algebra score of 10 and a mean geometry score of 13. Which graph shows the mean point marked with an X?

    Check

16. 16. The scatter graph shows the algebra and geometry test results of 10 learners. Both tests were marked out of 20. Use a line of best fit through the mean point (10, 13) to estimate (i) the geometry score of a learner who scored 6 in algebra, and (ii) the algebra score of a learner who scored 14 in geometry.

    • (i) about 10, (ii) about 11
    • (i) about 6, (ii) about 8
    • (i) about 14, (ii) about 14
    • (i) about 4, (ii) about 17
    Check

17. 17. The scatter graph shows the value of two-bedroom houses in a town and the distance of the houses from the railway station. What type of correlation does it show?

    • It can't be told.
    • positive correlation
    • no correlation
    • negative correlation
    Check

18. 18. The scatter graph shows the value of two-bedroom houses in a town and the distance of the houses from the railway station. One of the houses does not seem to fit the correlation. Which graph has the circle round that house?

    Check

19. 19. The scatter graph shows the value of two-bedroom houses in a town and the distance of the houses from the railway station. A line of best fit has been drawn. What is the equation, in the form y = mx + c, of this line?

    • y = −0.6x + 35
    • y = −0.16x + 35
    • y = −0.16x + 15
    • y = 0.16x + 35
    Check

20. 20. The scatter graph shows the value of two-bedroom houses in a town and the distance of the houses from the railway station. Use the line of best fit to estimate the value of y when x = 180.

    • about 2
    • about 10
    • about 14
    • about 6
    Check