In a hostel there were 100 students. To accommodate some more students the average budget is decreased by rupees 10. But total expenditure increased by Rs.400. If the total expenditure of the hostel now 5400, find the number of student joined?
Pick one:	A) 30	B) 20	C) 35	D) 32	E) 40

Rationale: let average is x 100 x + 400 = 5400 x = 50 let the number of student joined is y ( 100 + y ) * ( 50 - 10 ) = 5400 y = 35 answer : d
Answer: D