Mathematics
Average / Arithmetic Mean
A shop's average sales for 10 days are 210 units/day. On the last day it sold 145 units. What was the average for the first 9 days?
A. 217.22
B. 212.22
C. 222.22
D. 227.22
Correct Answer: A
First 9 days total = 10×210−145; average = 217.22.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 9 days are 200 units/day. On the last day it sold 140 units. What was the average for the first 8 days?
A. 207.5
B. 212.5
C. 217.5
D. 202.5
Correct Answer: A
First 8 days total = 9×200−140; average = 207.5.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 8 days are 190 units/day. On the last day it sold 135 units. What was the average for the first 7 days?
A. 192.86
B. 207.86
C. 202.86
D. 197.86
Correct Answer: D
First 7 days total = 8×190−135; average = 197.86.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 7 days are 180 units/day. On the last day it sold 130 units. What was the average for the first 6 days?
A. 188.33
B. 183.33
C. 198.33
D. 193.33
Correct Answer: A
First 6 days total = 7×180−130; average = 188.33.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 6 days are 170 units/day. On the last day it sold 125 units. What was the average for the first 5 days?
A. 189
B. 179
C. 184
D. 174
Correct Answer: B
First 5 days total = 6×170−125; average = 179.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 10 days are 160 units/day. On the last day it sold 120 units. What was the average for the first 9 days?
A. 159.44
B. 174.44
C. 169.44
D. 164.44
Correct Answer: D
First 9 days total = 10×160−120; average = 164.44.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 9 days are 150 units/day. On the last day it sold 115 units. What was the average for the first 8 days?
A. 164.38
B. 159.38
C. 154.38
D. 149.38
Correct Answer: C
First 8 days total = 9×150−115; average = 154.38.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 8 days are 140 units/day. On the last day it sold 110 units. What was the average for the first 7 days?
A. 139.29
B. 154.29
C. 144.29
D. 149.29
Correct Answer: C
First 7 days total = 8×140−110; average = 144.29.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 7 days are 130 units/day. On the last day it sold 105 units. What was the average for the first 6 days?
A. 144.17
B. 139.17
C. 129.17
D. 134.17
Correct Answer: D
First 6 days total = 7×130−105; average = 134.17.
Mathematics
Average / Arithmetic Mean
A shop's average sales for 6 days are 120 units/day. On the last day it sold 100 units. What was the average for the first 5 days?
A. 124
B. 119
C. 129
D. 134
Correct Answer: A
First 5 days total = 6×120−100; average = 124.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 44 runs after 17 innings. How many runs must he score next to raise the average to 46?
A. 80
B. 76
C. 88
D. 84
Correct Answer: A
Needed = (18×46)−(17×44) = 80.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 43 runs after 16 innings. How many runs must he score next to raise the average to 45?
A. 77
B. 73
C. 85
D. 81
Correct Answer: A
Needed = (17×45)−(16×43) = 77.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 42 runs after 15 innings. How many runs must he score next to raise the average to 44?
A. 82
B. 78
C. 74
D. 70
Correct Answer: C
Needed = (16×44)−(15×42) = 74.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 41 runs after 14 innings. How many runs must he score next to raise the average to 43?
A. 79
B. 67
C. 75
D. 71
Correct Answer: D
Needed = (15×43)−(14×41) = 71.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 40 runs after 13 innings. How many runs must he score next to raise the average to 42?
A. 64
B. 76
C. 72
D. 68
Correct Answer: D
Needed = (14×42)−(13×40) = 68.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 39 runs after 12 innings. How many runs must he score next to raise the average to 41?
A. 61
B. 73
C. 69
D. 65
Correct Answer: D
Needed = (13×41)−(12×39) = 65.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 38 runs after 11 innings. How many runs must he score next to raise the average to 40?
A. 58
B. 70
C. 62
D. 66
Correct Answer: C
Needed = (12×40)−(11×38) = 62.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 37 runs after 10 innings. How many runs must he score next to raise the average to 39?
A. 59
B. 67
C. 55
D. 63
Correct Answer: A
Needed = (11×39)−(10×37) = 59.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 36 runs after 9 innings. How many runs must he score next to raise the average to 38?
A. 56
B. 60
C. 52
D. 64
Correct Answer: A
Needed = (10×38)−(9×36) = 56.
Mathematics
Average / Arithmetic Mean
A batsman has an average of 35 runs after 8 innings. How many runs must he score next to raise the average to 37?
A. 53
B. 61
C. 49
D. 57
Correct Answer: A
Needed = (9×37)−(8×35) = 53.