Speed of a boat in standing water is 16 kmph and the speed of the stream is 2 kmph. A man rows to a place at a distance of 7020 km and comes back to the starting point. The total time taken by him is: Choose one.
A) 914.2 hours  B) 900 hours  C) 915 hours  D) 891.4 hours  E) 915 hours

Rationale: "explanation : speed downstream = ( 16 + 2 ) = 18 kmph speed upstream = ( 16 - 2 ) = 14 kmph total time taken = 7020 / 18 + 7020 / 14 = 390 + 501.4 = 891.4 hours answer : option d"
Answer: D