1. Problem Solving Using Percents
11.2
Problem Solving Using Percents

2. Percent: out of 100; per 100; part of 100
30% means 30 out of 100
Percent Problems:
a is p percent of b

3. a=part
b=whole
is means =
of means multiply
p=percent

4. You will know 2 of the 3 parts to solve the problems.

5. #1 What is 15% of 25? You don’t know the part.

6. #2 13 is 62% of what number? Don’t know whole or base.
Divide by 62
n=20.97

7. #3 125 is what percent of 86? Don’t know percent.
Divide by 86
p=145.3%

8. *Remember to move decimal 2 places to change decimal to %

9. Percent of increase or decrease
1. Find the difference between the original and final amount
2. Divide the difference by the original amount.
Increase/decrease
% of change =
Original

10. Example:
If the retail cost of a bike helmet is $38.95, and its wholesale cost is $22.75, what is the percent of markup?

11. 71% increase