A train speeds past a pole in 20 seconds and a platform 100 m long in 25 seconds. Its length is?  Options: A) 188 m B) 876 m C) 251 m D) 150 m E) 400 m
Let the length of the train be x meters and its speed be y m/sec.   They, x / y = 20 =&gt; y = x/20   x + 100 / 25 = x / 20   x = 400 m.   Answer: 400 m
<result>E</result>
A train speeds past a pole in 20 seconds and a platform 100 m long in 25 seconds. Its length is?