The task is to generate the correct answer for a given math problem.

[EX Q]: Problem: excluding stoppages , the average speed of a bus is 60 km / hr and including stoppages , the average speed of the bus is 15 km / hr . for how many minutes does the bus stop per hour ?
[EX A]: 4

[EX Q]: Problem: the volume of water inside a swimming pool doubles every hour . if the pool is filled to its full capacity within 8 hours , in how many hours was it filled to one quarter of its capacity ?
[EX A]: 6', 'e ) 7'

[EX Q]: Problem: a group of students decided to collect as many paise from each member of group as is the number of members . if the total collection amounts to rs . 72.25 , the number of the member is the group is :
[EX A]:
85