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

Input: Consider Input: Problem: arjun started a business with rs . 20,000 and is joined afterwards by anoop with rs . 80 , 000 . after how many months did anoop join if the profits at the end of the year are divided equally ?

Output: 9

Input: Consider Input: Problem: there are 7 executives , including the ceo and cfo , that are asked to form a small team of 4 members . however , the ceo and cfo may not both be assigned to the team . given this constraint , how many ways are there to form the team ?

Output: 25

Input: Consider Input: Problem: by selling 11 pencils for a rupee a man loses 10 % . how many for a rupee should he sell in order to gain 20 % ?
Output: 8.25