1. Finding a Percent of a Number
MCC6.RP.3c – Find a percent of a quantity as a rate per 100; solve problems involving finding the whole, given a part and the percent.

2. Writing a percent as a ratio
Write the percent over 100
Example: Write 15% as a ratio. 15
100

3. What is a proportion?
A proportion is 2 equal ratios

4. Using a Proportion to Find the Percent of a Number
Set up a proportion that uses the percent over 100.
Cross multiply to write an equation.
Solve the equation.
To set up your proportion, think, “IS over OF equals PERCENT over 100.”

5. Example – What is 20% of 30? x 20 = 30 100 100x = 30(20) 100x = 600
part = 30
100
whole
100x =
30(20)
100x =
600
100
100 x 6 =

6. Example:
What is 55% of 60?

7. Find the percent of a number by converting to a decimal.
1. Write the percent as a decimal.
2. Multiply

8. Example: What is 35% of 16? 35% converted to a decimal is .35
Multiply .35 x 16
35% of 16 is 5.6