Lesson objective: Analyze features of equivalent equations representing percent change.

Students practice calculating percent change by analyzing equations representing a real world situation. Ratio equations are used here to help students understand the connection between the values in a ratio and the percent change. This work develops students' understanding that equations can be set up in different ways to represent percent problems.

Students engage in Mathematical Practice 2: Students reason abstractly and quantitatively as they analyze algebraic equations to represent real-life situations involving percent.

**Key vocabulary:**

- percent change
- percent increase
- ratio equation

**Special materials needed:**

- graph paper
- calculators (as needed)