## Lesson: Percents

Developing the Concept

Now that students know how to find the amount of a tip, tax or discount using the formula *P* = *R* x *B,* it is time for them to solve for *B* given *P* and *R,* or solve for *R* given *P* and *B.*

**Preparation** Write the equation *P* = *R* x *B* on the board. Review what was done yesterday.

**Wrap-Up and Assessment Hints**

Getting students to recognize which piece of information is missing in a problem requires them to ask themselves what *P,* *R,* and *B* are for each problem. Have them verbalize this information and explain their reasoning.

Point out to students that some problems have more than one step. For example, in problems where they need to find the rate, or percent, of a discount, the original price and sale price may be given. Students will need to calculate the amount of the discount *before* using the formula. In problems where students are asked to find the sale price of an item, they need to subtract the amount of the discount from the original price after using the formula.