Speed of a boat in standing water is 8 kmph and the speed of the stream is 6 kmph. A man rows to place at a distance of 210 km and comes back to the starting point. The total time taken by him is:  Choose the correct choice from the following:
A) 120 hours	B) 240 hours	C) 160 hours	D) 480 hours	E) None
Sol.   Speed upstream = 2 kmph; Speed downstream = 14 kmph.   ∴ total time taken = [210/2 + 210/2] hours = 120 hours.   120 hoursnswer 120 hours
<result>A</result>
Speed of a boat in standing water is 8 kmph and the speed of the stream is 6 kmph. A man rows to place at a distance of 210 km and comes back to the starting point. The total time taken by him is: