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

Q: Problem: the cost of the paint is rs . 50 per kg . if 1 kg of paint covers 20 sq . ft , how much will it cost to paint outside of a cube having 20 feet each side

A: rs . 6000
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Q: Problem: in a new housing development , trees are to be planted along the sidewalk of a certain street . each tree takes up one square foot of sidewalk space , and there are to be 9 feet between each tree . how many trees can be planted if the road is 151 feet long ?

A: 1
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Q: Problem: if n is the smallest integer such that 72 times n is the square of an integer , what is the value of n ?

A:
2
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