A train 100m long takes 6 sec to cross a man walking at 5kmph in a direction opposite to that of the train. Find the speed of the train?
Choose the correct choice from the following choices:
A) 45kmph  B) 55kmph  C) 32kmph  D) 61kmph  E) 70kmph
Let the speed of the train be x kmph   Speed of the train relative to man = x+5 = (x+5)*5/18 m/sec   100/[(x+5)*5/18] = 6   30(x+5) = 1800   x = 55kmph   Answer is 55kmph
<result>B</result>
A train 100m long takes 6 sec to cross a man walking at 5kmph in a direction opposite to that of the train. Find the speed of the train?