A 300 meter long train crosses a platform in 42 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform?
Choose the correct choice from the following options:
A) 99
B) 289
C) 350
D) 882
E) 400
Speed = [300 / 18] m/sec = 50/3 m/sec.   Let the length of the platform be x meters.   Then, x + 300 / 42 = 50/3   3(x + 300) = 2100 è x = 400m.   Answer: 400
<result>E</result>
A 300 meter long train crosses a platform in 42 seconds while it crosses a signal pole in 18 seconds. What is the length of the platform?