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'.
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Question: Problem: if 28 % of a number exceeds 18 % of it by 7.2 , then find the number ? 
Options: a ) 50 , b ) 34 , c ) 55 , d ) 60 , e ) 90

Answer: e


Question: Problem: if 40 % of a certain number is 160 , then what is 30 % of that number ? 
Options: a ) 270 , b ) 380 , c ) 120 , d ) 360 , e ) 180

Answer: c


Question: Problem: a chemist mixes one liter of pure water with x liters of a 60 % salt solution , and the resulting mixture is a 10 % salt solution . what is the value of x ? 
Options: a ) 1 / 5 , b ) 1 / 3 , c ) 1 / 2 , d ) 1 , e ) 3

Answer:
a