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: if the cost price of 50 articles is equal to the selling price of 20 articles , then the gain or loss percent is ? 
Options: a ) 16 , b ) 127 , c ) 12 , d ) 18 , e ) 150

A: e
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Q: Problem: by selling 16 pens for a rupee a woman loses 5 % . how many for a rupee should he sell in order to gain 18 % ? 
Options: a ) 12 , b ) 14 , c ) 45 , d ) 13 , e ) 65

A: d
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Q: Problem: a reduction of 10 % in the price of tea enables a dealer to purchase 25 kg more tea for rs . 22500 . what is the reduced price per kg of tea ? 
Options: a ) rs . 70 , b ) rs . 80 , c ) rs . 90 , d ) rs . 100 , e ) none

A:
c
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