Hi Let s and c represent the speed(rowing) and the current respectively Question states*** NOte D/t = r s + c = 8kmph |40km/5hr = 8kmph s - c = 5kmph |40km/8hr = 5kmph 2s = 13 s = 13/2 or 6.5mph c = 1.5mph | (8kmph-s) from 1st Eq