The task is to generate the correct answer for a given math problem.
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Question: Problem: 20 is subtracted from 80 % of a number , the result is 60 . find the number ?

Answer: 100


Question: Problem: by selling an article for $ 225 a person gains $ 75 . what is the gain % ?

Answer: 50 %


Question: Problem: every disk in a bag is either blue , yellow or green . the ratio of blue disks to yellow disks to green disks in this bag is 3 : 7 : 8 . if the total number of disks in the bag is 126 , how many more green disks than blue disks are in the bag ?

Answer:
35