Statistics Practice Test

Name: ______________________   Date: __________   Score: ____ / 32

32 questions. Calculator allowed. Show your working. steplyclass.com/statistics/practice-test/

1. 1

   Bar chart: Mon 5, Tue 3, Wed 7; how many in all

   Answer: ____________________

2. 2

   Dot plot of 3, 5, 4, 6, 5, 7, 5, 4, 6, 5, 8, 5; how many are 6 or more

   Answer: ____________________

3. 3

   Histogram of 12, 25, 31, 18, 27, 22, 35, 29, 15, 24 classes of 10; how many are 20 or more

   Answer: ____________________

4. 4

   Histogram of 72, 85, 91, 68, 77, 83, 95, 79, 88, 74, 81, 86, 69, 92 classes of 10; how many are 80 or more

   Answer: ____________________

5. 5

   Find the mean of grouped data 0-10: 3, 10-20: 7, 20-30: 6, 30-40: 4.
   1. A) mean ≈ 20
   2. B) mean ≈ 5
   3. C) mean ≈ 102.5
   4. D) mean ≈ 20.5

6. 6

   Find the mean of grouped data 0-1: 5, 1-2: 8, 2-3: 4, 3-4: 3.

   Answer: ____________________

7. 7

   Histogram: class 20-40 has frequency density 1.5, find the frequency
   1. A) −30
   2. B) 32
   3. C) 30
   4. D) 20

8. 8

   Histogram: class 40-100 has frequency density 0.25, find the frequency
   1. A) 14
   2. B) 60
   3. C) −1500
   4. D) 15

9. 9

   Calculate 50th percentile of 3, 5, 6, 8, 9, 12, 15

   Answer: ____________________

10. 10

    Percentile of 30 in 30, 25, 18, 30, 40, 35, 22, 30, 28, 45, 33, 20

    Answer: ____________________

11. 11

    Cumulative frequency: 0-10: 4, 10-20: 9, 20-30: 15, 30-40: 8, 40-50: 4, find the median
    1. A) −247
    2. B) 24.7
    3. C) −24.7
    4. D) −2.47

12. 12

    Cumulative frequency: 20-40: 10, 40-60: 30, 60-80: 25, 80-100: 15, find the lower quartile

    Answer: ____________________

13. 13

    Outliers in 2, 15, 17, 18, 20, 21, 23, 45
    1. A) 2
    2. B) 45
    3. C) 2 and 45

14. 14

    Outliers in 0, 10, 11, 12, 13, 14, 15, 16, 30

    Answer: ____________________

15. 15

    Population standard deviation of 4, 8, 6, 5, 7
    1. A) SD ≈ 6
    2. B) SD ≈ 1.4
    3. C) SD ≈ 14
    4. D) SD ≈ 2

16. 16

    Sample standard deviation of 48, 52, 50, 46, 54

    Answer: ____________________

17. 17

    Scatter plot (1, 2) (2, 4) (3, 5) (4, 4) (5, 7) (6, 8)
    1. A) Positive correlation
    2. B) Negative correlation
    3. C) No correlation

18. 18

    Scatter plot height vs shoe size: (150, 36) (155, 38) (160, 39) (165, 41) (170, 42) (175, 44)
    1. A) Positive correlation
    2. B) Negative correlation
    3. C) No correlation

19. 19

    Correlation coefficient of (1, 2) (2, 4) (3, 6) (4, 8) (5, 10)
    1. A) r = 20
    2. B) r = 120
    3. C) r = 3
    4. D) r = 1

20. 20

    Correlation coefficient of (2, 3) (3, 6) (5, 4) (6, 9) (9, 8)

    Answer: ____________________

21. 21

    Line of best fit (1, 2) (2, 4) (3, 5) (4, 4) (5, 7)

    Answer: ____________________

22. 22

    Line of best fit (10, 50) (20, 45) (30, 42) (40, 30) (50, 28), predict x = 60

    Answer: ____________________

23. 23

    Line of best fit y = 2x + 1, point (3, 8), find the residual

    Answer: ____________________

24. 24

    Line of best fit y = −x + 6, point (1, 3), find the residual

    Answer: ____________________

25. 25

    Scatterplot (0, 2) (1, 4) (2, 8) (3, 16) (4, 32): linear or exponential
    1. A) Linear
    2. B) Exponential

26. 26

    Scatterplot (0, 1.5) (1, 3) (2, 6.1) (3, 11.9) (4, 24.2): linear or exponential
    1. A) Linear
    2. B) Exponential

27. 27

    Normal mean 50 sd 5, percent between 45 and 55
    1. A) 68%
    2. B) 6800%
    3. C) 0.15%
    4. D) 34%

28. 28

    Normal mean 160 sd 7, percent between 153 and 174

    Answer: ____________________

29. 29

    Calculate z-score of 62, mean 50, sd 8
    1. A) 1.5
    2. B) 55.75
    3. C) 15
    4. D) −1.5

30. 30

    Find the value with z = 2.5, mean 150, sd 12.

    Answer: ____________________

31. 31

    A survey says 52% with a margin of error of 3%. Is 50% a plausible value?
    1. A) Yes
    2. B) No

32. 32

    The mean in a sample is 12.6 with a margin of error of 1.2. Is 14 a plausible value for the mean?
    1. A) Yes
    2. B) No