A train speeds past a pole in 15 seconds and a platform 100 m long in 25 seconds. Its length is:
Select
A) 100 m  B) 125 m  C) 130 m  D) 150 m  E) 160 m
Explanation:   Let the length of the train be x meters and its speed be y m/sec.   They, x / y = 15 =&gt; y = x/15   x + 100 / 25 = x / 15   x = 150 m.   ANSWER IS 150 m
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A train speeds past a pole in 15 seconds and a platform 100 m long in 25 seconds. Its length is: