1. Adding and Subtracting Percents
Tax, Tip and Discount
Adding and Subtracting Percents

2. Adding Percents
When we are adding a percentage onto an original amount, we can add the percent to 100%.
This can be used to find the total amount after some percentage has been added. (ex. Tax)
Takes one step out of solving problems.
Ex. You are buying a shirt that costs $12 with a 2.6% sales tax.
100% + 2.6% = % = (decimal)
12 * = ≈ $12.31

3. Practice
Sarah is buying a new pair of shoes for $ The sales tax is 8.3%. How much will she pay?
2. At Alex’s furniture store, they charge a 12% sales tax. If a bed frame costs $226, how much will the consumer pay in total?

4. Subtracting Percents
When we are taking away a certain percentage from an original amount, we can subtract the percent from 100%.
This can be used to find the total amount after some percentage has been subtracted. (ex. discounts)
Takes one step out of solving problems.
Ex. These $45 shorts are on sale for 20% off. How much do they cost?
100% - 20% = 80% = 0.80 (decimal)
45 * 0.80 = $36

5. Practice
At Camilla's antique shop, everything is 30% off. How much will I pay for a table that costs $147.50?
After a 15% off sale, some jeans were $ how much were the jeans before the sale?
100% - 15% = 85%
11.50 = 85% of the total cost
Set up a proportion and solve!