Master ACT Geometry with Our Statistics Practice Test/Quiz

Report a question

What's wrong with this question?
You cannot submit an empty report. Please add some details.

30 random questions |30 minutes | Questions are randomized every attempt. Good luck!

ACT Math - Statistics Practice Test

Test your ACT statistics skills with 30 random test practice questions covering mean, median, mode, and probability!

1 / 30

1. From a standard deck, P(red and face card)?

A) 1/4

B) 3/26

C) 6/52

D) 6/26

Red face cards=6. P=6/52=3/26.

2 / 30

2. In a normal distribution, what percent of data is below the mean?

A) 50%

B) 25%

C) 68%

D) 75%

Normal distribution is symmetric about the mean — 50% below.

3 / 30

3. What is the median of 7,2,9,4,6,1,8?

A) 4

B) 5

C) 6

D) 7

Sorted: 1,2,4,6,7,8,9. Median=6.

4 / 30

4. What is the formula for the geometric mean of n numbers?

A) (x₁+x₂+...+xₙ)/n

B) ⁿ√(x₁×x₂×...×xₙ)

C) Product/n

D) Sum/n

Geometric mean = nth root of the product.

5 / 30

5. If the mean is 25 and the SD is 5, what is the z-score for x=35?

A) 3

B) 2

C) 4

D) 1

z=(35-25)/5=10/5=2.

6 / 30

6. What is the mean absolute deviation of 2, 4, 6, 8?

A) 3

B) 4

C) 1

D) 2

Mean=5. Deviations:|2-5|=3,|4-5|=1,|6-5|=1,|8-5|=3. MAD=(3+1+1+3)/4=2.

7 / 30

7. In a set of 7 numbers, the mean is 14. One number is removed; new mean is 12. What was removed?

A) 30

B) 28

C) 26

D) 24

Sum=98. New sum with 6 values at mean 12=72. Removed=26.

8 / 30

8. How many different 5-digit PINs allow repetition?

A) 50000

B) 90000

C) 100000

D) 120

10⁵=100000.

9 / 30

9. What is the IQR of 3,7,11,15,19,23,27?

A) 8

B) 20

C) 16

D) 12

Q1=7, Q3=23. IQR=16.

10 / 30

10. Ten numbers have a mean of 8. What is their sum?

A) 80

B) 85

C) 75

D) 70

Sum=8×10=80.

11 / 30

11. A data set: 10,20,30,40,50. What is the mean?

A) 25

B) 35

C) 30

D) 40

Mean=(10+20+30+40+50)/5=150/5=30.

12 / 30

12. In a data set, if every value increases by 5, what happens to the standard deviation?

A) Doubles

B) Increases by 25

C) Increases by 5

D) Stays the same

Adding a constant shifts data but doesn't change spread — SD stays the same.

13 / 30

13. What is the range of 50, 20, 80, 30, 60, 40?

A) 65

B) 50

C) 55

D) 60

Range = 80 - 20 = 60.

14 / 30

14. What is P(A∪B) if P(A)=0.4, P(B)=0.5, P(A∩B)=0.2?

A) 0.7

B) 0.9

C) 0.6

D) 0.8

0.4+0.5-0.2=0.7.

15 / 30

15. In 100 tosses of a coin, expected heads?

A) 75

B) 50

C) 25

D) 100

Expected=100×0.5=50.

16 / 30

16. What does a positive correlation mean in a scatter plot?

A) As x increases, y increases

B) The data is perfectly linear

C) As x increases, y decreases

D) No relationship

Positive correlation: both variables increase together.

17 / 30

17. What is the outlier rule using IQR?

A) Outside 2 SDs

B) Outside 1 SD from mean

C) Below Q1 or above Q3

D) Below Q1-1.5×IQR or above Q3+1.5×IQR

Outlier if Q3+1.5(IQR).

18 / 30

18. How many 3-digit numbers can be formed using digits 1,2,3,4 without repetition?

A) 12

B) 24

C) 16

D) 32

P(4,3) = 4×3×2 = 24.

19 / 30

19. What is the mean of the data 0,0,0,12?

A) 12

B) 3

C) 4

D) 0

12/4=3.

20 / 30

20. A student got 80 on 4 tests. What score on the 5th test gives an 82 average?

A) 88

B) 91

C) 89

D) 90

Need total=82×5=410. Current=320. Need 410-320=90.

21 / 30

21. Two events: P(A|B)=P(A). What can we say?

A) B is impossible

B) A and B are independent

C) A and B are mutually exclusive

D) A is certain

P(A|B)=P(A) means B doesn't affect A: independent.

22 / 30

22. A die is rolled 60 times. Expected number of 4s?

A) 8

B) 12

C) 6

D) 10

Expected = 60 × 1/6 = 10.

23 / 30

23. A die is rolled 4 times. Expected number of 3s?

A) 1/6

B) 4

C) 2/3

D) 1

E=4×1/6=4/6=2/3.

24 / 30

24. What is the mean of the data: 1,4,9,16,25?

A) 9

B) 11

C) 10

D) 15

(1+4+9+16+25)/5=55/5=11.

25 / 30

25. If the mean is 50 and SD is 10, what is the z-score for x = 65?

A) 2.5

B) 1.0

C) 2.0

D) 1.5

z = (65-50)/10 = 15/10 = 1.5.

26 / 30

26. How many ways to select a committee of 4 from 9 people?

A) 126

B) 252

C) 36

D) 63

C(9,4)=126.

27 / 30

27. What is the median of 11, 13, 15, 17, 19, 21?

A) 18

B) 15

C) 16

D) 17

Even count: (15+17)/2 = 16.

28 / 30

28. What is the complement of P(rolling a 1) on a die?

A) 1/6

B) 5/6

C) 1

D) 0

P(not 1)=1-1/6=5/6.

29 / 30

29. What is the variance of 2,4,6?

A) 4/3

B) 8/3

C) 3

D) 4

Mean=4. Deviations: -2,0,2. Squared: 4,0,4. Variance=8/3.

30 / 30

30. C(6,2) = ?

A) 18

B) 30

C) 15

D) 12

6!/(2!4!)=15.

Your score is
The average score is 70%
0%

🎯 Register FREE to save your score and unlock 1000+ more free quizzes!

👉 Register Now — It’s Free!

📚 StudyRightWay

Pages

Resources

Legal

Connect

Course has been added to your cart