Civil Service Numerical Reasoning Test Basic Statistics 4 — Questions and Answers
Question 1: Data set: 4, 8, 15, 16, 23, 42. What is the median?
- 15.5 (Correct answer)
- 15
- 16
- 17
Correct answer: 15.5
With 6 values, median = mean of 3rd and 4th values. (15 + 16) ÷ 2 = 15.5.
Question 2: Monthly temperatures (°C): 8, 10, 14, 18, 22, 25, 26, 24, 19, 13, 9, 7. What is the range?
- 19 (Correct answer)
- 18
- 20
- 21
Correct answer: 19
Range = 26 − 7 = 19.
Question 3: Seven values: 12, 15, 11, 18, 12, 20, 14. What is the mode?
- 12 (Correct answer)
- 14
- 15
- 11
Correct answer: 12
12 appears twice (more than any other value). The mode is 12.
Question 4: A manager reviews call times (minutes): 3, 5, 8, 4, 6, 5, 7, 5. What is the mean?
- 5.375 (Correct answer)
- 5
- 5.5
- 6
Correct answer: 5.375
Sum = 3 + 5 + 8 + 4 + 6 + 5 + 7 + 5 = 43. Mean = 43 ÷ 8 = 5.375.
Question 5: Weekly outputs: 120, 135, 110, 145, 130. What is the mean weekly output?
- 128 (Correct answer)
- 130
- 125
- 135
Correct answer: 128
Sum = 120 + 135 + 110 + 145 + 130 = 640. Mean = 640 ÷ 5 = 128.
Question 6: Data: 9, 12, 15, 12, 18, 9, 12, 21. What is the mode?
- 12 (Correct answer)
- 9
- 15
- 18
Correct answer: 12
12 appears three times — more than 9 (twice) or any others. The mode is 12.
Civil Service Numerical Reasoning Test Basic Statistics 4
Data set: 4, 8, 15, 16, 23, 42.
What is the median?