A 200 meter long train crosses a platform in 50 seconds while it crosses a signal pole in 42 seconds. What is the length of the platform? Pick one:	A) 39.9	B) 37.88	C) 35	D) 38.88	E) 38.09

Rationale: "speed = [ 200 / 42 ] m / sec = 100 / 21 m / sec . let the length of the platform be x meters . then , x + 200 / 50 = 100 / 21 21 ( x + 200 ) = 5000 è x = 38.09 m . answer : e"
Answer: E