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

Ex Input:
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 Output:
4


Ex Input:
Problem: if 2 men or 3 women can reap a field in 10 days how long will 4 men and 5 women take to reap it ?

Ex Output:
11 / 30


Ex Input:
Problem: evaluate ( 12 + 22 + 32 + . . . + 102 )

Ex Output:

385