A 750 m long train crosses a platform in 39 sec while it crosses a signal pole in 18 sec. What is the length of the platform? Choose the correct choice from the following answers.
A) 300 B) 875 C) 360 D) 770 E) 380
Speed = 750/18 = 125/3 m/sec.   Let the length of the platform be x meters.   Then, (x + 750)/39 = 125/3   =&gt; x = 1625 m.   L=1625-750= 
<gadget id="calculator">1625-750</gadget>
<output>875</output>
875   Answer: Option 875
<result>B</result>
A 750 m long train crosses a platform in 39 sec while it crosses a signal pole in 18 sec. What is the length of the platform?