Analyze proportional relationships and use them to solve real-world and mathematical problems.
Recognize and represent proportional relationships between quantities. (7.RP.2)
c. Represent proportional relationships by equations. For example, if total cost t is proportional to the number n of items purchased at a constant price p, the relationship between the total cost and the number of items can be expressed as t = pn. (7.RP.2c)
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