a boat can travel with aspeed of 30 km / hr in still water . if the speed of the stream is 5 km / hr , find the time taken by the boat to go 70 km downstream .
"speed downstream = ( 30 + 5 ) km / hr = 35 km / hr . time taken to travel 68 km downstream = 70 / 35 hrs = 2 hrs . b"
divide(70, add(30, 5))