1. Using Proportions to Solve Percent Problems MCC7.RP.3: Use proportional relationships to solve multistep ratio and percent problems. Examples: simple interest, tax, markups and markdowns, gratuities and commissions, fees, percent increase and decrease, percent error.

2. What are they?? What do you know about these examples? simple interest, tax, markups and markdowns, gratuities and commissions, fees, percent increase and decrease, percent error.

3. Use this proportion to solve percent problems:

4. Using Proportions to Solve Percent Problems The original price of a cell phone is $99.50. Sales tax is 7%. What is the selling price of the cell phone? Percent Part 7%x 100 Whole100 99.50

5. Using Proportions to Solve Percent Problems **Cross multiply to solve** 7%x 100 99.50 (7) (99.50) = 100x 696.50 = 100x *divide by 100 6.97 = x *tax is $6.97. Add to original price of cell phone. 99.50 + 6.97 = 106.47 Selling price of cell phone is $106.47

6. Using Proportions to Solve Percent Problems You try one! A shirt that is originally $24.95 is on sale for a discount of 20%. What is the selling price of the shirt before tax?

7. Using Proportions to Solve Percent Problems Tax is 6%. What is the total cost to purchase the shirt?