If the average marks of three batches of 60, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is Answers:	A) 53.33	B) 54.54	C) 55	D) 57	E) None
Sol.   Required average = [60x50 + 60x55 + 45x60 / 60 + 60 + 45]   = [3000 + 3300 + 2700 / 165]   = 9000 / 165 = 54.54.   Answer 54.54
<result>B</result>
If the average marks of three batches of 60, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is