Trains Q52

52.	A train speeds past a pole in 15 seconds and a platform 100 m long in 25 seconds. Its length is:
	A. 50 m B. 150 m C. 200 m D. Data inadequate

Answer: Option B

Explanation:

Let the length of the train be x metres and its speed by y m/sec.

Then,	x	= 15       ==>     y =	x	.
	y		15

	x + 100	=	x
	25		15

 15(x + 100) = 25x

 15x + 1500 = 25x

 1500 = 10x

                     x = 150 m.