Excluding stoppages, the average speed of a bus is 60 km/hr and including stoppages, the average speed of the bus is 45 km/hr. For how many minutes does the bus stop per hour? Pick:
A) 15 B) 88 C) 77 D) 20 E) 99
In 1hr, the bus covers 60 km without stoppages and 45 km with stoppages.   Stoppage time = time take to travel (60 - 45) km i.e 15 km at 60 km/hr.   stoppage time = 15/60 hrs = 15 min.   15nswer: 15
<result>A</result>
Excluding stoppages, the average speed of a bus is 60 km/hr and including stoppages, the average speed of the bus is 45 km/hr. For how many minutes does the bus stop per hour?