A train running at 54 kmph takes 20 seconds to pass a platform. Next it takes.12 sec to pass a man walking at 6 kmph in the same direction in which the train is going. Find the length of the train and the length of the platform  Select
A) 120m
B) 125m
C) 132m
D) 140m
E) 150m
Explanation:   Let the length of train be x metres and length of platform be y metres.   Speed of the train relative to man = (54 - 6)= 
<gadget id="calculator">(54 - 6)</gadget>
<output>48</output>
48 kmph= 48×(5/18) m/sec = 40/3 m/sec.   In passing a man, the train covers its own length with relative speed.   Length of train = (Relative speed × Time) = ( 40/3)×12 m = 160 m.   Also, speed of the train = 54 ×(5/18)m / sec = 15 m / sec.   (x+y)/15 = 20 &lt;=&gt; x + y = 300 &lt;=&gt; Y = (300 - 160)= 
<gadget id="calculator">(300 - 160)</gadget>
<output>140</output>
140 m.   Answer: Option 140m
<result>D</result>
A train running at 54 kmph takes 20 seconds to pass a platform. Next it takes.12 sec to pass a man walking at 6 kmph in the same direction in which the train is going. Find the length of the train and the length of the platform