speed of a boat in standing water is 9 kmph and the speed of the stream is 1 . 5 kmph . a man rows to a place at a distance of 105 km and comes back to the starting point . the total time taken by him is
"upstream = 9 kmph - 1.5 kmph = 7.5 kmph downstream = 9 kmph + 1.5 kmph = 10.5 kmph total time taken = 105 / 7.5 + 105 / 10.5 = 24 hrs answer : d"
add(divide(5, add(9, 1)), divide(5, subtract(9, 1)))