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

Q: Problem: the sum of all the digits of the integers from 18 to 21 inclusive is 24 ( 1 + 8 + 1 + 9 + 2 + 0 + 2 + 1 = 24 ) . what is the sum t of all the digits of the integers from 0 to 99 inclusive ?

A: 900
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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: a sum fetched a total simple interest of rs . 144 at the rate of 15 p . c . p . a . in 1 year 6 months . what is the sum ?

A:
640
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