Here are two stories: The initial freshman class at a college is 10% smaller than last year’s class. But then during the first week of classes, 20 more students enroll. There are then 830 students in the freshman class. A store reduces the price of a computer by $20. Then during a 10% off sale, a customer pays $830

here are two equations: 0.9x+20=830, 0.9(x-20)=830

A. Decide which equation represents each story.

B. Explain why one equation has parentheses and the other doesn't.

C. Solve each equation, and explain what was the solution means in the situation.

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