A 300 m long train crosses a platform in 51 sec while it crosses a signal pole in 18 sec. What is the length of the platform?  Choose the correct choice from the following answers:
A) 287	B) 350	C) 828	D) 277	E) 550
Speed = 300/18 = 50/3 m/sec.   Let the length of the platform be x meters.   Then, (x + 300)/5A = 50/3   3x + 900 = 2550 =&gt; x = 550 m.   Answer: 550
<result>E</result>
A 300 m long train crosses a platform in 51 sec while it crosses a signal pole in 18 sec. What is the length of the platform?