How many seconds will a 620 metre long train take to cross a man running with a speed of 8 km/hr in the direction of the moving train if the speed of the train is 80 km/hr? Choose the most appropriate option.
A) 25 B) 30 C) 31 D) 45 E) 60
Explanation :   Speed of train relatively to man = ( 80- 8)km/hr   = 72 km /hr   = (72 x 5 / 18)m/sec   = 20 m/sec   Time taken to pass the man = (620/ 20)= 
<gadget id="calculator">(620/ 20)</gadget>
<output>31</output>
31 sec.   Answer : 31
<result>C</result>
How many seconds will a 620 metre long train take to cross a man running with a speed of 8 km/hr in the direction of the moving train if the speed of the train is 80 km/hr?