Mathematics
Average / Arithmetic Mean
A section of 22 members has mean 42. Another section of 6 members with mean 62 is merged into it. What is the resulting mean?
A. 47.29
B. 48.29
C. 46.29
D. 45.29
Correct Answer: C
Resulting mean = (22×42+6×62)/28 = 46.29.
Mathematics
Average / Arithmetic Mean
A section of 21 members has mean 41. Another section of 5 members with mean 61 is merged into it. What is the resulting mean?
A. 43.85
B. 45.85
C. 46.85
D. 44.85
Correct Answer: D
Resulting mean = (21×41+5×61)/26 = 44.85.
Mathematics
Average / Arithmetic Mean
A section of 20 members has mean 40. Another section of 4 members with mean 60 is merged into it. What is the resulting mean?
A. 45.33
B. 43.33
C. 42.33
D. 44.33
Correct Answer: B
Resulting mean = (20×40+4×60)/24 = 43.33.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 4, 7, 12 and respective averages 29, 44, 59. Find their combined mean.
A. 51.22
B. 50.22
C. 49.22
D. 48.22
Correct Answer: C
Combined mean = Σ(size×mean)/Σsize = 49.22.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 6, 6, 11 and respective averages 28, 43, 58. Find their combined mean.
A. 45.26
B. 46.26
C. 48.26
D. 47.26
Correct Answer: B
Combined mean = Σ(size×mean)/Σsize = 46.26.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 5, 9, 10 and respective averages 27, 42, 57. Find their combined mean.
A. 46.12
B. 45.12
C. 44.12
D. 47.12
Correct Answer: B
Combined mean = Σ(size×mean)/Σsize = 45.12.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 4, 8, 9 and respective averages 26, 41, 56. Find their combined mean.
A. 43.57
B. 45.57
C. 44.57
D. 46.57
Correct Answer: C
Combined mean = Σ(size×mean)/Σsize = 44.57.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 6, 7, 8 and respective averages 25, 40, 55. Find their combined mean.
A. 43.43
B. 40.43
C. 41.43
D. 42.43
Correct Answer: C
Combined mean = Σ(size×mean)/Σsize = 41.43.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 5, 6, 12 and respective averages 24, 39, 54. Find their combined mean.
A. 42.57
B. 44.57
C. 45.57
D. 43.57
Correct Answer: D
Combined mean = Σ(size×mean)/Σsize = 43.57.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 4, 9, 11 and respective averages 23, 38, 53. Find their combined mean.
A. 43.38
B. 41.38
C. 42.38
D. 44.38
Correct Answer: C
Combined mean = Σ(size×mean)/Σsize = 42.38.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 6, 8, 10 and respective averages 22, 37, 52. Find their combined mean.
A. 41.5
B. 40.5
C. 39.5
D. 38.5
Correct Answer: C
Combined mean = Σ(size×mean)/Σsize = 39.5.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 5, 7, 9 and respective averages 21, 36, 51. Find their combined mean.
A. 39.86
B. 37.86
C. 38.86
D. 40.86
Correct Answer: C
Combined mean = Σ(size×mean)/Σsize = 38.86.
Mathematics
Average / Arithmetic Mean
Three teams have sizes 4, 6, 8 and respective averages 20, 35, 50. Find their combined mean.
A. 38.33
B. 39.33
C. 37.33
D. 40.33
Correct Answer: A
Combined mean = Σ(size×mean)/Σsize = 38.33.
Mathematics
Average / Arithmetic Mean
One batch averages 33 and another averages 72. Their combined mean is 56.4. In what ratio are the batch sizes (first:second)?
A. 4:7
B. 6:4
C. 5:6
D. 4:6
Correct Answer: D
By alligation, first:second = (72−56.4):(56.4−33) = 4:6.
Mathematics
Average / Arithmetic Mean
One batch averages 32 and another averages 70. Their combined mean is 55.75. In what ratio are the batch sizes (first:second)?
A. 5:3
B. 4:5
C. 3:6
D. 3:5
Correct Answer: D
By alligation, first:second = (70−55.75):(55.75−32) = 3:5.
Mathematics
Average / Arithmetic Mean
One batch averages 31 and another averages 68. Their combined mean is 45.8. In what ratio are the batch sizes (first:second)?
A. 7:4
B. 6:5
C. 6:4
D. 4:6
Correct Answer: C
By alligation, first:second = (68−45.8):(45.8−31) = 6:4.
Mathematics
Average / Arithmetic Mean
One batch averages 30 and another averages 66. Their combined mean is 43.5. In what ratio are the batch sizes (first:second)?
A. 5:4
B. 3:5
C. 5:3
D. 6:3
Correct Answer: C
By alligation, first:second = (66−43.5):(43.5−30) = 5:3.
Mathematics
Average / Arithmetic Mean
One batch averages 29 and another averages 64. Their combined mean is 40.67. In what ratio are the batch sizes (first:second)?
A. 2:4
B. 4:2
C. 4:3
D. 5:2
Correct Answer: B
By alligation, first:second = (64−40.67):(40.67−29) = 4:2.
Mathematics
Average / Arithmetic Mean
One batch averages 28 and another averages 62. Their combined mean is 50.67. In what ratio are the batch sizes (first:second)?
A. 6:3
B. 3:6
C. 4:6
D. 3:7
Correct Answer: B
By alligation, first:second = (62−50.67):(50.67−28) = 3:6.
Mathematics
Average / Arithmetic Mean
One batch averages 27 and another averages 60. Their combined mean is 42. In what ratio are the batch sizes (first:second)?
A. 5:6
B. 7:5
C. 6:6
D. 6:5
Correct Answer: D
By alligation, first:second = (60−42):(42−27) = 6:5.