1. Using Proportions – Less 6.6
Percent Proportions
Using Proportions – Less 6.6

2. Vocabulary Review
Ratio: The comparison of two numbers (written in Algebra as a fraction) Proportion: When two ratios are equal to each other Cross Product(s): When we cross multiply/compare diagonally, the special relationship between two ratios in a proportion

3. Percent Proportions
Proportions can be used to solve missing percentages of a number… “is #” = given/missing % “of #” 100%

4. Percent Proportions Ex. Find 30% of 24. x = 30% 24 100% Ex.
Cross multiply
Divide to solve
We use the same steps to solve…
Ex.
Find 30% of 24.
Is # =
Of # =
Given/missing % =
Write out proportion…
x = % %
*Round answer to nearest tenth of percent!
Ex.
What percent is 20 of 210?
Is # =
Of # =
Given/missing % =
Write out proportion… =
100%
*Round answer to nearest tenth of percent!

5. Percent Proportions Ex. What is 33% of 150? Ex.
% =
x = % %
Ex.
5 is 80% of what number?
Is # =
Of # =
% =
5 = %
x %

6. Practice 6% of what number is 2.46 What percent of 72 is 27?
Write a proportion to solve. When necessary, round to the nearest tenth.
6% of what number is 2.46
What percent of 72 is 27?
Find 72% of 310.

7. Homework
p #14-19, 21, 42, 43, 45 (Calculator okay!) Show set up/process/work