excluding stoppages , the speed of a bus is 60 kmph and including stoppages , it is 45 kmph . for how many minutes does the bus stop per hour ?
"due to stoppages , it covers 15 km less . time taken to cover 15 km = ( 15 / 60 x 60 ) min = 15 min answer : e"
multiply(const_60, divide(subtract(60, 45), 60))