Lesson objective: Fluently multiply and divide within a table to find a ratio to help write an algebraic expression.

This lesson helps to build fluency with writing expressions. A table is used here because it highlights the relationship within the ratio. This work develops students' understanding that mathematical relationships can be represented with expressions, and we can use those expressions as we use numbers.

Students engage in Mathematical Practice 2 (Reason abstractly and quantitatively) as they turn numerical data from a table into an algebraic expression showing a proportional relationship.

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