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

Q: Problem: if a - b = 6 and a 2 + b 2 = 50 , find the value of ab .

A: a ) 7
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Q: Problem: a = 5 ^ 10 - 625 ^ 2 and a / x is an integer , where x is a positive integer greater than 1 , such that it does not have a factor p such that 1 < p < x , then how many different values for x are possible ?

A: two
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Q: Problem: if rs . 10 be allowed as true discount on a bill of rs . 110 due at the end of a certain time , then the discount allowed on the same sum due at the end of double the time is :

A:
rs . 18.33
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