A train passes a station platform in 48 seconds and a man standing on the platform in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?	Pick one:
A) 123 B) 166 C) 420 D) 157 E) 198
Speed = [54 * 5/18] m/sec = 15 m/sec.   Length of the train = (15 * 20)= 
<gadget id="calculator">(15 * 20)</gadget>
<output>300</output>
300 m.   Let the length of the platform be x meters.   Then, (x + 300) / 48= 15   x + 300 = 720   x = 420 m.   Answer: 420
<result>C</result>
A train passes a station platform in 48 seconds and a man standing on the platform in 20 seconds. If the speed of the train is 54 km/hr, what is the length of the platform?