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'.

[EX Q]: Problem: if the simple interest on a certain sum of money for 5 years is one – fifth of the sum , then the rate of interest per annum is 
Options: a ) 4 % , b ) 7 % , c ) 6 % , d ) 4 % , e ) 3 %
[EX A]: d

[EX Q]: Problem: a total of $ 20,000 was invested in two certificates of deposit at simple annual interest rates of 4 percent and 8 percent , respectively . if the total interest on the two certificates was $ 1,440 at the end of one year , what fractional part of the $ 20.000 was invested at the higher rate ? 
Options: a ) 3 / 8 , b ) 4 / 5 , c ) 1 / 2 , d ) 3 / 5 , e ) 3 / 4
[EX A]: b

[EX Q]: Problem: the owner of a furniture shop charges his customer 10 % more than the cost price . if a customer paid rs . 8800 for a computer table , then what was the cost price of the computer table ? 
Options: a ) rs . 6725 , b ) rs . 6727 , c ) rs . 8000 , d ) rs . 6725 , e ) rs . 6728
[EX A]:
c