Trains Q50

50.	A 300 metre long train crosses a platform in 39 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform?
	A. 320 m B. 350 m C. 650 m D. Data inadequate

Answer: Option B

Explanation:

Speed =		300		m/sec =	50	m/sec.
		18			3

Let the length of the platform be x metres.

Then,		x + 300		=	50
		39			3

 3(x + 300) = 1950

                     x = 350 m.