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'.
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Question: 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 %

Answer: d


Question: Problem: jar a has 6 % more marbles than jar b . what percent of marbles from jar a need to be moved into jar b so that both jars have equal marbles ? 
Options: a ) 2.8 % , b ) 3.0 % , c ) 3.2 % , d ) 3.4 % , e ) 3.6 %

Answer: a


Question: Problem: the cost price of an article is 55 % of the marked price . calculate the gain percent after allowing a discount of 15 % . 
Options: a ) 40.5 % , b ) 48.7 % , c ) 54.5 % , d ) 55.6 % % , e ) none

Answer:
c