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

Q: Problem: a man rows his boat 110 km downstream and 90 km upstream , taking 3 hours each time . find the speed of the stream ?

A: 3.5
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Q: Problem: sachin is older than rahul by 7 years . if the ratio of their ages is 11 : 9 , find the age of sachin

A: 38.5
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Q: Problem: a 80 cm long wire is to be cut into two pieces so that one piece will be 3 / 5 th of the other , how many centimeters will the shorter piece be ?

A:
a ) 30
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