Big Ideas:
Ratios are multiplicative relationships between two or more quantities that are related.
Ratios describe a relationship that remains constant as total quantities are increased or decreased.
Some situations represent relationships between quantities that are not ratio relationships.
In this lesson, students are given an opportunity to distinguish between ratio and non-ratio situations. Students evaluate situations in which relationships exist between quantities and determine whether they are ratio relationships or not based upon an evaluation of the mathematical structure of the relationships. Specifically, students will look for common equivalent ratios and consistent multiplicative relationships. This lesson builds upon future work in proportionality and linear functions.
Vocabulary: for every, per, and standard ratio notation including '3:1' and 3 to 1'
Special Materials:
none
Lesson plan