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

Q: Problem: a jar contains a mixture of ab in the ratio 4 : 1 . when 40 l of mixture is replaced with liquid b , ratio becomes 2 : 3 . how many liters of liquid a was present in mixture initially .

A: 64
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Q: Problem: a is twice as good a workman as b and they took 6 days together to do the work b alone can do it in .

A: 18 days
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Q: Problem: 3 friends had dinner at a restaurant . when the bill was received , akshitha paid 3 / 4 as much as veena paid and veena paid 1 / 2 as much as lasya paid . what fraction of the bill did veena pay ?

A:
4 / 15
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