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

Q: Problem: a can do a piece of work in 80 days . he works at it for 10 days b alone finishes the remaining work in 42 days . in how much time will a and b working together , finish the work ?

A: 30
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Q: Problem: in how many no . between 10 and 30 exactly two of the digits is 2 ?

A: 1
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Q: Problem: 1391 x 1391 = ?

A:
e ) 193488
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