A train speeds past a pole in 15 sec and a platform 150 m long in 25 sec, its length is?  Pick one.
A) 238  B) 150  C) 988  D) 177  E) 225
Let the length of the train be x m and its speed be y m/sec.   Then, x/y = 15 =&gt; y = x/15   (x + 150)/25 = x/15 =&gt; x = 225 m.   Answer: 225
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A train speeds past a pole in 15 sec and a platform 150 m long in 25 sec, its length is?