Students should understand that two variables show direct variation if y = kx and k is not equal to zero. k represents the constant of proportionality. In the equation, the two variables, y and x, vary directly to each other as they represent proportional relationships.
The number of calories consumed from a fun size piece of candy is directly proportional to the number of candies eaten. If 3 candies contain 24 calories, how many candies would you have to eat to consume 960 calories? Justify your thinking.
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8.5 Proportionality. The student applies mathematical process standards to use proportional and non-proportional relationships to develop foundational concepts of functions. The student is expected to:
(E) solve problems involving direct variation