If the average marks of three batches of 45, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is
Choose one:
A) 53.33	B) 54.68	C) 55	D) 57	E) None
Sol.   Required average = [55x50 + 60x55 + 45x60 / 45 + 60 + 45]   = [2250 + 3300 + 2700 / 150]   = 8250 / 150= 
<gadget id="calculator">8250 / 150</gadget>
<output>55</output>
55   Answer 55
<result>C</result>
If the average marks of three batches of 45, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is