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 man has $ 10,000 to invest . he invests $ 4000 at 5 % and $ 3500 at 4 % . in order to have a yearly income of $ 500 , he must invest the remainder at : 
Options: a ) 4.6 % , b ) 3.6 % , c ) 6.4 % , d ) 7.8 % , e ) 8.9 %

Answer: c


Question: Problem: 90 students represent x percent of the boys at jones elementary school . if the boys at jones elementary make up 40 % of the total school population of x students , what is x ? 
Options: a ) 125 , b ) 150 , c ) 225 , d ) 250 , e ) 500

Answer: b


Question: Problem: increasing the original price of an article by 20 percent and then increasing the new price by 20 percent is equivalent to increasing the original price by 
Options: a ) 40 % , b ) 41 % , c ) 42 % , d ) 43 % , e ) 44 %

Answer:
e