A train speeds past a pole in 10 seconds and a platform 100 m long in 30 seconds. Its length is? Choices
A) 188 m B) 876 m C) 251 m D) 50 m E) 45 m
Let the length of the train be x meters and its speed be y m/sec.   They, x / y = 10 =&gt; y = x/10   x + 100 / 30 = x / 10   x = 50 m.   Answer: 50 m
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A train speeds past a pole in 10 seconds and a platform 100 m long in 30 seconds. Its length is?