A train speeds past a pole in 15 sec and a platform 100 m long in 25 sec, its length is? Choose the most appropriate option.
A) 140
B) 150
C) 160
D) 170
E) 180
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 + 100)/25 = x/15 =&gt; x = 150 m.   Answer: Option 150
<result>B</result>
A train speeds past a pole in 15 sec and a platform 100 m long in 25 sec, its length is?