Averages Q30

30. If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55, 60, then the average marks of all the students is:

A. 53.33                   B.54.68

C.55                         D.None of these

Answer: Option B

Explanation:

Required average	= 55 x 50 + 60 x 55 + 45 x 60 55 + 60 + 45
	= 2750 + 3300 + 2700 160
	= 8750 160
	= 54.68