Lesson objective: Calculate probabilities of complementary events and events that use "or."

This lesson helps to build procedural skill with finding probabilities. Ratios and percents are used because probabilities can be represented, added, and subtracted with these rational number representations. This work develops students' understanding that probabilities with more than one favorable outcome can be added, and complementary events can be found by subtracting from 1 whole.

Students engage in Mathematical Practice 4 (Model with mathematics) as they use ratios to represent and calculate probabilities of various flavor combinations in a bag of fruit chews.

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