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'.

[EX Q]: Problem: if an article is sold at 18 % profit instead of 9 % profit , then the profit would be $ 54 more . what is the cost price ? 
Options: a ) $ 500 , b ) $ 600 , c ) $ 700 , d ) $ 800 , e ) $ 900
[EX A]: b

[EX Q]: Problem: there were two candidates in an election . winner candidate received 62 % of votes and won the election by 384 votes . find the number of votes casted to the winning candidate ? 
Options: a ) 288 , b ) 744 , c ) 992 , d ) 298 , e ) 177
[EX A]: c

[EX Q]: Problem: in a certain pond , 30 fish were caught , tagged , and returned to the pond . a few days later , 50 fish were caught again , of which 2 were found to have been tagged . if the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond , what is the approximate number of fish in the pond ? 
Options: a ) 750 , b ) 625 , c ) 1,250 , d ) 2,500 , e ) 10,000
[EX A]:
a