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

Q: Problem: jack and jill are marathon runners . jack can finish a marathon ( 42 km ) in 7 hours and jill can run a marathon in 4.2 hours . what is the ratio of their average running speed ? ( jack : jill )

A: 5 / 5
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Q: Problem: find compound interest on $ 10000 at 15 % per annum for 2 years 4 months , compounded annually .

A: 3886.25
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Q: Problem: a rectangular field has a length 10 meters more than it is width . if the area of the field is 119 , what is the length ( in meters ) of the rectangular field ?

A:
17
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