The task is to generate the correct answer for a given math problem.
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Question: Problem: a can do a work in 15 days and b in 20 days . if they work on it together for 5 days , then the fraction of the work that is left is

Answer: 5 / 12


Question: Problem: the owner of a furniture shop charges his customer 25 % more than the cost price . if a customer paid rs . 1000 for a computer table , then what was the cost price of the computer table ?

Answer: 80


Question: Problem: find the cost of fencing around a circular field of diameter 32 m at the rate of rs . 2 a meter ?

Answer:
201