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

[EX Q]: Problem: a and b can do a work in 5 days and 10 days respectively . a starts the work and b joins him after 2 days . in how many days can they complete the remaining work ?
[EX A]: 2

[EX Q]: Problem: how many zeroes are there at the end of the number n , if n = 70 ! + 140 ! ?
[EX A]: 16

[EX Q]: Problem: find the greatest number which leaves the same remainder when it divides 25 , 57 and 105 .
[EX A]:
16