Two trains A and B are 175 m and 150 m long and are moving at one another at 54 Km/hr and 36 Km/hr respectively. Arun is sitting on coach B1 of train A. Calculate the time taken by Arun to completely cross Train B.	Choose the most appropriate option:
A) 10 s  B) 6 s  C) 4 s  D) 8 s  E) 13 s
DETAILED SOLUTION   Speed of A = 54∗1000/60∗60 = 15 m/s   Speed of B = 36∗1000/60∗60 = 10 m/s   Relative speed = S1 + S2 = 15 + 10 m/s = 25 m/s   The length that needs to be crossed = length of train B = 150 m. Therefore time taken = 150/25= 
<gadget id="calculator">150/25</gadget>
<output>6</output>
6s.   What is the time taken for trains to completely cross each other? The length that needs to be crossed= 175 + 150= 
<gadget id="calculator">175 + 150</gadget>
<output>325</output>
325 m. Time taken=325/25= 
<gadget id="calculator">325/25</gadget>
<output>13</output>
13 s.   CORR13 sCT ANSW13 sR 13 s.
<result>E</result>
Two trains A and B are 175 m and 150 m long and are moving at one another at 54 Km/hr and 36 Km/hr respectively. Arun is sitting on coach B1 of train A. Calculate the time taken by Arun to completely cross Train B.