1. Lesson 7.5 Percent of Change
Essential Question: How do you solve problems with percent of increase or decrease?

2. Before we start…
You bought a pair of jeans for $20 on clearance. If the original price is $40. What percent is the clearance sale?

3. Percent of Change
A percent of change shows how much a quantity has increased or decreased from the original amount.
Today’s gas prices are 67% higher than in 2009.

4. What’s a percent of increase?
The new amount is greater than the original amount.
Gas prices today are $3.83. Last week prices were $3.79.

5. What’s a percent of decrease?
The new amount is less than the original amount.
In the state funding for school was $6,317,098. for the state funding for school is $5,742,728.

6. How do you solve problems with a percent of increase or decrease?
You will use the percent of change formula to solve these problems.

7. How do you find a percent of change?=
amount of increase or decrease original amount

8. Bears During the summer, a bear’s heart rate is about 60 beats per minute, but it can drop to as low as 8 beats per minute during the winter. What is the percent of change in a bear’s heart rate from the summer rate to the winter rate?

9. School Enrollment A school had 825 students enrolled last year
School Enrollment A school had 825 students enrolled last year. This year, 870 students are enrolled. Find the percent of increase to the nearest tenth.

10. National Parks From October to November one year, attendance at Everglades National Park increased about 27.4%. There were 59,084 visitors in October. To the nearest hundred, how many people visited in November?

11. Camera Sale A camera is on sale for 10% off $170, and you have a coupon for an extra 10% off. How much will this camera cost?

12. Actors An acting club had 24 members last year
Actors An acting club had 24 members last year. This year it has 30 members. Find the percent of increase.

13. Population In 2000, a town’s population was 1260
Population In 2000, a town’s population was In 2006, the population was What is the percent of decrease in the town’s population?

14. Sales A real estate agent sells 32 properties one year
Sales A real estate agent sells 32 properties one year. The next year, the agent sells 54 properties. Find the percent of increase.

15. Banking Two years ago, your savings account balance was $492. 19
Banking Two years ago, your savings account balance was $ Since then, the balance has increased 32.6%. What is the current balance?

16. Population From 1990 to 2000, there was a 1
Population From 1990 to 2000, there was a 1.5% decrease in the population of Pittsburgh, Pennsylvania. The population of Pittsburgh was 2,394,811 in What was the population in 2000?

17. How do you solve problems with percent of increase or decrease?

18. Ticket Out the Door
Find the percent of increase or decrease. From 50 to 36.