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: increasing the original price of an article by 6 percent and then increasing the new price by 6 percent is equivalent to increasing the original price by 
Options: a ) 12.1 % , b ) 12.36 % , c ) 12.94 % , d ) 13.65 % , e ) 14.56 %

A: b
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Q: Problem: increasing the original price of a certain item by 25 percent and then increasing the new price by 30 percent is equivalent to increasing the original price by what percent ? 
Options: a ) 31.25 , b ) 37.5 , c ) 50.0 , d ) 52.5 , e ) 62.5

A:
e
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