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: the salary of a person was reduced by 10 % . by what percent should his reduced salary be raised so as to bring it at par with his original salary ? 
Options: a ) 10 % , b ) 11 1 / 9 % , c ) 13 2 / 7 % , d ) 15 3 / 11 % , e ) 12 1 / 3 %

Answer: b


Question: Problem: two numbers are respectively 50 % and 100 % more than a third number . the percentage that is first of the second is ? 
Options: a ) 65 % , b ) 83 % , c ) 27 % , d ) 42 % , e ) 75 %

Answer: e


Question: Problem: peter invests a sum of money and gets back an amount of $ 830 in 3 years . david invests an equal amount of money and gets an amount of $ 854 in 4 years . if both amounts were invested at the same rate ( simple interest ) what was the sum of money invested ? 
Options: a ) 670 , b ) 664 , c ) 698 , d ) 758 , e ) 700

Answer:
d