excluding the stoppages , the speed of a bus is 48 km / hr and including the stoppages the speed of the bus is 12 km / hr . for how many minutes does the bus stop per hour ?
"speed of the bus without stoppage = 48 km / hr speed of the bus with stoppage = 12 km / hr difference in speed = 36 km / hr so , the time taken in the stoppages = time taken to cover 36 km = ( 36 / 48 ) hr = 3 / 4 hr = 45 min answer : a"
subtract(const_60, multiply(divide(12, 48), const_60))