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'.

Q: Problem: a sum of money at simple interest amounts to rs . 815 in 3 years and to rs . 865 in 4 years . the sum is : 
Options: a ) s . 665 , b ) s . 690 , c ) s . 698 , d ) s . 700 , e ) s . 720

A: a
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Q: Problem: a man took loan from a bank at the rate of 12 % p . a . s . i . after 10 years he had to pay rs . 1500 interest only for the period . the principal amount borrowed by him was ? 
Options: a ) 1502 , b ) 1900 , c ) 1250 , d ) 1750 , e ) 2000

A: c
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Q: Problem: a number exceeds 20 % of itself by 40 . the number is ? 
Options: a ) 50 , b ) 60 , c ) 80 , d ) 320 , e ) none

A:
a
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