A train speeds past a pole in 15 sec and a platform 140 m long in 25 sec, its length is? Choose the correct choice from the following options: A) 238 B) 150 C) 988 D) 210 E) 171
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 + 140)/25 = x/15 =&gt; x = 210 m.   Answer: 210
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A train speeds past a pole in 15 sec and a platform 140 m long in 25 sec, its length is?