Overview
Practice
Watch
Read
Quiz
Next Steps
Overview
7th Grade Math
Proportionality
6. TX.7.4.D
6.6 Adding and multiplying percents
Adding and Multiplying Percentages
How to add percentages of the same whole and multiply a percent of a percent.
What You'll Learn
Add percentages only when they are parts of the same whole (e.g. tax plus tip).
Multiply a percent of a percent by changing each to a decimal and multiplying.
Example: 50% of 20% = 0.5 times 0.2 = 0.10 = 10%.
To find a percent of a number, convert the percent to a decimal and multiply.
Successive discounts multiply, not add: 20% off then 10% off is 28% off, not 30%.
What You'll Practice
1
Calculating sales tax on purchases and finding total cost after tax
2
Computing sequential percentage increases across multiple time periods
3
Solving compound interest problems over multiple years
4
Determining actual percentage change between initial and final values
Why This Matters
Understanding how to add and multiply percentages is essential for managing your finances, from calculating sales tax on purchases to understanding how your savings grow with compound interest. These skills help you make informed decisions about spending, saving, and comparing deals in everyday situations.
Before You Start — Make Sure You Can:
This Unit Includes
5 Video lessons
Practice exercises
Learning resources
Skills
Percentages
Sales Tax
Compound Interest
Decimal Conversion
Sequential Calculations
Word Problems
Financial Math
TX Curriculum Aligned