In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: if 40 % of a certain number is 160 , then what is 30 % of that number ? 
Options: a ) 270 , b ) 380 , c ) 120 , d ) 360 , e ) 180

A: c
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Q: Problem: at what rate percent per annum will the simple interest on a sum of money be 4 / 5 of the amount in 10 years ? 
Options: a ) 4 % , b ) 7 % , c ) 8 % , d ) 3 % , e ) 1 %

A: c
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Q: Problem: a sum fetched total simple interest of 4016.25 at the rate of 10 p . c . p . a . in 5 years . what is the sum ? 
Options: a ) 8925 , b ) 8032.5 , c ) 4462.5 , d ) 8900 , e ) none of these

A:
b
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