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: what annual installment will discharge a debt of rs . 1428 due in 3 years at 12 % simple interest ? 
Options: a ) 315 , b ) 345 , c ) 425 , d ) 335 , e ) none of them

Answer: c


Question: 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 %

Answer: d


Question: Problem: when the price of a radio was reduced by 20 % , its sale increased by 80 % . what was the net effect on the sale ? 
Options: a ) 44 % increase , b ) 44 % decrease , c ) 66 % increase , d ) 75 % increase , e ) none of these

Answer:
a