Question

Sam wanted to know how much the price of milk had changed over the last few decades.He found that the price of a gallon of milk was $0.80 in 1970 and in 1990 it was $1.20.What was the average rate of change in a gallon of milk per year?

Answer 1

2 cents

Explanation:

because it was 40 cents in 20 years and 2x20=40

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