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: 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

A: c
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Q: Problem: at a particular graduation party with 300 guests , 70 % of the guests brought gifts , and 40 % of the female guests brought gifts . if 30 males did not bring gifts to the party , how many females did bring gifts ? 
Options: a ) 18 , b ) 28 , c ) 40 , d ) 68 , e ) 70

A: c
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Q: Problem: an article is sold at a certain price . by selling it at 2 / 3 of that price one loses 10 % . find the gain percent at original price . 
Options: a ) 15 % , b ) 35 % , c ) 25 % , d ) 50 % , e ) 30 %

A:
b
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