An education center offers a total of 400 math, physics and
chemistry courses. The ratio of the number of math to physics
to chemistry courses is 3:4:3.
The cost of a math class is $25 per class and the cost of a
physics class is $20 per class. If you took all 400 classes, it
would cost a total of $9,800. What is the price of each
chemistry class?
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