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: a family made a down payment of $ 300 and borrowed the balance on a set of encyclopedias that cost $ 750 . the balance with interest was paid in 9 monthly payments of $ 57 each and a final payment of $ 21 . the amount of interest paid was what percent of the amount borrowed ? 
Options: a ) 6 % , b ) 12 % , c ) 14 % , d ) 18.66 % , e ) 20 %

A: d
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Q: Problem: the difference between simple and compound interest on rs . 1600 for one year at 10 % per annum reckoned half - yearly is ? 
Options: a ) 8 , b ) 3 , c ) 9 , d ) 4 , e ) 2

A: d
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Q: Problem: by selling 14 pencils for a rupee a man loses 20 % . how many for a rupee should he sell in order to gain 20 % ? 
Options: a ) 28 , b ) 26 , c ) 25 , d ) 23 , e ) 21

A:
e
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