Mathematics
Average / Arithmetic Mean
A dataset contains 8 observations whose sum is 228. Determine its mean.
A. 32.5
B. 26.5
C. 28.5
D. 30.5
Correct Answer: C
Mean = 228 ÷ 8 = 28.5.
Mathematics
Average / Arithmetic Mean
A dataset contains 7 observations whose sum is 204. Determine its mean.
A. 27.14
B. 33.14
C. 29.14
D. 31.14
Correct Answer: C
Mean = 204 ÷ 7 = 29.14.
Mathematics
Average / Arithmetic Mean
A dataset contains 6 observations whose sum is 180. Determine its mean.
A. 30
B. 28
C. 32
D. 34
Correct Answer: A
Mean = 180 ÷ 6 = 30.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 10 observations: 42, 45, 48, 40, 43, 46, 49, 41, 44, 47.
A. 48.5
B. 42.5
C. 44.5
D. 46.5
Correct Answer: C
Add all 10 observations and divide by 10: 445 ÷ 10 = 44.5.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 8 observations: 39, 42, 45, 37, 40, 43, 46, 38.
A. 39.25
B. 43.25
C. 45.25
D. 41.25
Correct Answer: D
Add all 8 observations and divide by 8: 330 ÷ 8 = 41.25.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 6 observations: 36, 39, 42, 45, 37, 40.
A. 39.83
B. 41.83
C. 37.83
D. 43.83
Correct Answer: A
Add all 6 observations and divide by 6: 239 ÷ 6 = 39.83.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 10 observations: 33, 36, 39, 42, 34, 37, 40, 43, 35, 38.
A. 39.7
B. 41.7
C. 35.7
D. 37.7
Correct Answer: D
Add all 10 observations and divide by 10: 377 ÷ 10 = 37.7.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 8 observations: 41, 33, 36, 39, 31, 34, 37, 40.
A. 38.38
B. 36.38
C. 40.38
D. 34.38
Correct Answer: B
Add all 8 observations and divide by 8: 291 ÷ 8 = 36.38.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 6 observations: 38, 30, 33, 36, 39, 31.
A. 32.5
B. 38.5
C. 34.5
D. 36.5
Correct Answer: C
Add all 6 observations and divide by 6: 207 ÷ 6 = 34.5.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 10 observations: 35, 27, 30, 33, 36, 28, 31, 34, 37, 29.
A. 34
B. 36
C. 32
D. 30
Correct Answer: C
Add all 10 observations and divide by 10: 320 ÷ 10 = 32.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 8 observations: 32, 35, 27, 30, 33, 25, 28, 31.
A. 28.12
B. 32.12
C. 30.12
D. 34.12
Correct Answer: C
Add all 8 observations and divide by 8: 241 ÷ 8 = 30.12.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 6 observations: 29, 32, 24, 27, 30, 33.
A. 31.17
B. 27.17
C. 33.17
D. 29.17
Correct Answer: D
Add all 6 observations and divide by 6: 175 ÷ 6 = 29.17.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 10 observations: 26, 29, 21, 24, 27, 30, 22, 25, 28, 31.
A. 30.3
B. 28.3
C. 26.3
D. 24.3
Correct Answer: C
Add all 10 observations and divide by 10: 263 ÷ 10 = 26.3.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 8 observations: 23, 26, 29, 21, 24, 27, 19, 22.
A. 25.88
B. 27.88
C. 21.88
D. 23.88
Correct Answer: D
Add all 8 observations and divide by 8: 191 ÷ 8 = 23.88.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 6 observations: 20, 23, 26, 18, 21, 24.
A. 26
B. 24
C. 20
D. 22
Correct Answer: D
Add all 6 observations and divide by 6: 132 ÷ 6 = 22.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 10 observations: 17, 20, 23, 15, 18, 21, 24, 16, 19, 22.
A. 23.5
B. 21.5
C. 17.5
D. 19.5
Correct Answer: D
Add all 10 observations and divide by 10: 195 ÷ 10 = 19.5.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 8 observations: 14, 17, 20, 23, 15, 18, 21, 13.
A. 17.62
B. 19.62
C. 21.62
D. 15.62
Correct Answer: A
Add all 8 observations and divide by 8: 141 ÷ 8 = 17.62.
Mathematics
Average / Arithmetic Mean
Find the arithmetic mean of these 6 observations: 11, 14, 17, 20, 12, 15.
A. 18.83
B. 14.83
C. 16.83
D. 12.83
Correct Answer: B
Add all 6 observations and divide by 6: 89 ÷ 6 = 14.83.
Mathematics
Average / Arithmetic Mean
The average of 4 numbers is 25. If a fifth number is included, the average becomes 28. What is the fifth number?
A. 42
B. 44
C. 38
D. 40
Correct Answer: D
Old total 100; new total 140; fifth = 40.
Mathematics
Average / Arithmetic Mean
A car travels 120 km at 40 km/h and returns 120 km at 60 km/h. What is its average speed?
A. 50 km/h
B. 52 km/h
C. 48 km/h
D. 46 km/h
Correct Answer: C
Equal distances: 2×40×60/(40+60)=48 km/h.