a man can row downstream at the rate of 18 kmph and upstream at 6 kmph . find the man ’ s rate in still water and rate of current ?
"rate of still water = 1 / 2 ( down stream + upstream ) = 1 / 2 ( 18 + 6 ) = 12 kmph rate of current = 1 / 2 ( down stream - upstream ) = 1 / 2 ( 18 - 6 ) = 1 / 2 ( 12 ) = 6 kmph answer is b ."
divide(subtract(18, 6), const_2)