excluding stoppages , the speed of a bus is 60 kmph and including stoppages , it is 50 kmph . for how many minutes does the bus stop per hour ?
"due to stoppages , it covers 10 km less . time taken to cover 10 km = ( 10 / 60 x 60 ) min = 10 min answer : a"
multiply(const_60, divide(subtract(60, 50), 60))