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 present worth of rs . 2310 due years hence , the rate of interest being 15 % per annum , is : 
Options: a ) rs . 1440 , b ) rs . 1750 , c ) rs . 1680 , d ) rs . 1840 , e ) none of these

Answer: c


Question: Problem: what will be the difference between simple and compound interest at 16 % per annum on a sum of rs . 1000 after 4 years ? 
Options: a ) 164.19 , b ) 164.12 , c ) 170.6 , d ) 167.1 , e ) 165.11

Answer: c


Question: Problem: if 5 % more is gained by selling an book for $ 350 than by selling it for $ 340 , the cost of the book is : 
Options: a ) 500 , b ) 400 , c ) 200 , d ) 300 , e ) 100

Answer:
c