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

Q: Problem: the area of a circular field is 17.56 hectares . find the cost of fencing it at the rate of rs . 7 per metre approximately

A: 10400
****
Q: Problem: how many numbers between 400 and 1000 can be made with the digits 2 , 3,4 , 5,6 and 0 ?

A: 60
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Q: Problem: two pipes a and b can separately fill a tank in 12 and 15 minutes respectively . a third pipe c can drain off 56 liters of water per minute . if all the pipes are opened , the tank can be filled in 15 minutes . what is the capacity of the tank ?

A:
672
****