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

Q: Problem: audrey 4 hours to complete a certain job . ferris can do the same job in 3 hours . audrey and ferris decided to collaborate on the job , working at their respective rates . while audrey worked continuously , ferris took 5 breaks of equal length . if the two completed the job together in 2 hours , how many minutes long was each of ferris ’ breaks ?

A: 6
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Q: Problem: if a 1 mm thick paper is folded so that the area is halved at every fold , then what would be the thickness of the pile after 50 folds ?

A: 1 billion km', 'e ) none'
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Q: Problem: a shopkeeper sold an article at $ 1170 and gained a 20 % profit . what was the cost price ?

A:
$ 975
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