a boat goes 100 km downstream in 10 hours , and 75 m upstream in 15 hours . the speed of the stream is ?
100 - - - 10 ds = 10 ? - - - - 1 75 - - - - 15 us = 5 ? - - - - - 1 s = ( 10 - 5 ) / 2 = 2 21 / 2 kmph answer : d
divide(subtract(divide(100, 10), divide(75, 15)), const_2)