A 300 m long train crosses a platform in 27 sec while it crosses a signal pole in 18 sec. What is the length of the platform?
Choose the correct choice
A) 286 m
B) 350 m
C) 277 m
D) 278 m
E) 150 m

Rationale: "speed = 300 / 18 = 50 / 3 m / sec . let the length of the platform be x meters . then , ( x + 300 ) / 27 = 50 / 3 x = 150 m . answer : e"
Answer: E