A 300 m long train crosses a platform in 39 sec while it crosses a signal pole in 18 sec. What is the length of the platform? Choose the correct choice from the following choices:
A) 389 m B) 350 m C) 289 m D) 299 m E) 219 m
Speed = 300/18 = 50/3 m/sec.   Let the length of the platform be x meters.   Then, (x + 300)/39 = 50/3   3x + 900 = 1950 =&gt; x = 350 m.   Answer:350 m
<result>B</result>
A 300 m long train crosses a platform in 39 sec while it crosses a signal pole in 18 sec. What is the length of the platform?