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: 40 is subtracted from 70 % of a number , the result is 30 . find the number ?
Options: a ) 150 , b ) 997 , c ) 266 , d ) 288 , e ) 100

Answer: e

Question: Problem: by selling an article for $ 90 , a person gains $ 15 . what is the gain % ?
Options: a ) 25 % , b ) 30 % , c ) 50 % , d ) 20 % , e ) 10 %

Answer: d

Question: Problem: sandy had $ 210 left after spending 30 % of the money she took for shopping . how much money did sandy take along with her ?
Options: a ) $ 240 , b ) $ 300 , c ) $ 360 , d ) $ 420 , e ) $ 480

Answer:
b