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: an error 10 % in excess is made while measuring the side of a square . now what is the percentage of error in the calculated area of the square ? 
Options: a ) 6.64 % , b ) 16.64 % , c ) 15.64 % , d ) 21 % , e ) 10.64 %

A: d
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Q: Problem: jar a has 26 % 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 ) 7.6 % , b ) 8.3 % , c ) 9.6 % , d ) 10.3 % , e ) 11.5 %

A: d
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Q: Problem: how much 60 % of 50 is greater than 42 % of 30 ? 
Options: a ) 18 , b ) 91 , c ) 11 , d ) 17.4 , e ) 12

A:
d
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