A train crosses a pole in 15 seconds and a platform 100

A train crosses a pole in 15 seconds and a platform 100 metres long in 25 seconds. Its length (in metres) is

Let the length of train be x metre.

∴	x	=	x + 100
	15		25

⇒	x	=	x + 100
	3		5

⇒ 5x = 3x + 300
⇒ 2x = 300

⇒ x =	300	= 150 metres
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