The task is to generate the correct answer for a given math problem.
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Question: Problem: maxwell leaves his home and walks toward brad ' s house at the same time that brad leaves his home and runs toward maxwell ' s house . if the distance between their homes is 72 kilometers , maxwell ' s walking speed is 6 km / h , and brad ' s running speed is 12 km / h . what is the distance traveled by maxwell when they meet in the middle ?

Answer: 24


Question: Problem: by selling an article for $ 195 , a person gains $ 45 . what is the gain % ?

Answer: 30 %


Question: Problem: find the ratio in which rice at rs . 7.10 a kg be mixed with rice at rs . 5.70 a kg to produce a mixture worth rs . 6.30 a kg ?

Answer:
3 : 4