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

Q: Problem: if a drawing has an outer circle of diameter 30 and an inner circle of diameter 24 , then what fraction of outer circle ' s surface is not covered by the inner circle ?

A: 9 / 25', 'e ) 2 / 3'
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Q: Problem: a is half good a work man as b and together they finish a job in 14 days . in how many days working alone b finish the job ?

A: 21
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Q: Problem: sarah operated her lemonade stand monday through friday over a two week period and made a total profit of 210 dollars . on hot days she sold cups of lemonade for a price that was 25 percent higher than the regular days . each cup she sold had a total cost of 75 cents and sarah did not incur any other costs . if every day she sold exactly 32 cups and 3 of the days were hot , then what was the price of 1 cup on a hot day ?

A:
$ 1.64
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