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: at what rate percent per annum will the simple interest on a sum of money be 2 / 5 of the amount in 10 years ? 
Options: a ) 4 % , b ) 74 % , c ) 64 % , d ) 74 % , e ) 94 %

Answer: a


Question: Problem: a $ 500 investment and a $ 1,500 investment have a combined yearly return of 16 percent of the total of the two investments . if the $ 500 investment has a yearly return of 7 percent , what percent yearly return does the $ 1,500 investment have ? 
Options: a ) 9 % , b ) 10 % , c ) 105 / 8 % , d ) 11 % , e ) 19 %

Answer: e


Question: Problem: the balance of a trader weighs 20 % less than it should . still the trader marks up his goods to get an overall profit of 30 % . what is the mark up on the cost price ? 
Options: a ) 4 % , b ) 8 % , c ) 25 % , d ) 16.66 % , e ) 9 %

Answer:
a