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

Q: Problem: how many integers k greater than 100 and less than 700 are there such that if the hundreds and the unit digits of k are reversed , the resulting integer is k + 99 ?

A: 50
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Q: Problem: if z is a multiple of 8778 , what is the remainder when z ^ 2 is divided by 9 ?

A: 0
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Q: Problem: if the average ( arithmetic mean ) of a and b is 45 and the average of b and c is 80 , what is the value of c − a ?

A:
60
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