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

Q: Problem: if a - b = 5 and a 2 + b 2 = 31 , find the value of ab .

A: 3
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Q: Problem: the ratio of a to b is 4 to 5 , where a and b are positive . if x equals a increased by 25 percent of a , and m equals b decreased by 60 percent of b , what is the value of m / x ?

A: 2 / 5
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Q: Problem: a certain article of clothing was discounted during a special sale to 3 / 4 of its original retail price . when the clothing did n ' t sell , it was discounted even further to 1 / 3 of its original retail price during a second sale . by what percent did the price of this article of clothing decrease from the first sale to the second sale ?

A:
55.55 %
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