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'.

Input: Consider Input: Problem: if the cost price of 55 articles is equal to the selling price of 50 articles , then what is the percent profit ?
Options: a ) 5 % , b ) 10 % , c ) 15 % , d ) 20 % , e ) 25 %

Output: b

Input: Consider Input: Problem: a , b and c start a business each investing 20,000 . after 10 months a withdrew 5000 , b withdrew 4000 and c invests 6000 more . at the end of the year , a total profit of 71400 was recorded . find the share of b .
Options: a ) 20,000 , b ) 21,200 , c ) 23,200 , d ) 20,500 , e ) none of these

Output: c

Input: Consider Input: Problem: a chemist mixes one liter of pure water with x liters of a 50 % salt solution , and the resulting mixture is a 10 % salt solution . what is the value of x ?
Options: a ) 1 / 4 , b ) 1 / 3 , c ) 1 / 2 , d ) 1 , e ) 3
Output: a