Excluding the stoppages, the speed of a bus is 32 km/hr and including the stoppages the speed of the bus is 16 km/hr. For how many minutes does the bus stop per hour?	Pick one
A) 15 min  B) 10 min  C) 12 min  D) 30 min  E) 18 min

Rationale: "speed of the bus without stoppage = 32 km / hr speed of the bus with stoppage = 16 km / hr difference in speed = 16 km / hr so , the time taken in the stoppages = time taken to cover 16 km = ( 16 / 32 ) hr = 1 / 2 hr = 30 min answer : d"
Answer: D