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: at what rate of compound interest per annum will a sum of rs . 1200 become rs . 1348.32 in 2 years 
Options: a ) 3 % , b ) 4 % , c ) 5 % , d ) 6 % , e ) 7 %

A: d
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Q: Problem: rs . 200 amounts to rs . 800 in 8 years at simple interest . if the interest is increased by 5 % , it would amount to how much ? 
Options: a ) 520 , b ) 440 , c ) 260 , d ) 280 , e ) 120

A: d
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Q: Problem: a man buy a book in rs 50 & sale it rs 90 . what is the rate of profit ? ? ? 
Options: a ) 10 % , b ) 80 % , c ) 30 % , d ) 25 % , e ) 28 %

A:
b
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