Facebook

Year Friends

Amount of change =

Percent of change is a ratio that compares the change in quantity to the original amount. (What percent of the original amount changed?)

% of change =

How many more friends did _____________ have in __________ than in _________?

Facebook

Year Friends

Amount of change =

Percent of change is a ratio that compares the change in quantity to the original amount. (What percent of the orginal amount changed?)

% of change =

How many more friends did _____________ have in __________ than in _________?

Then/Now

You have already solved real world problems using the percent proportion.

• Find percent of increase and decrease. (Lesson 7.6)

Facebook

Year Friends

Amount of change =

% of change =

Find the percent of change from 20 students to 24 students. State whether the percent of change is an increase or decrease.

Step 1 Subtract to find the amount of change.24 – 20 = 4

Step 2 Set up a percent proportion with a ratio that compares the amount of change to the original amount. Express you result as a percent.

Pedro had 325 trading cards. He now has 270 trading cards. Find the percent of change. Round to the nearest tenth, if necessary. Then state whether the percent of change is an increase or decrease.

Step 1 Subtract to find the amount of change.

Step 2 Set up a percent proportion with a ratio that compares the amount of change to the original amount. Express you result as a percent.

A. AB. BC. CD. D

Example 1

A B C D

0% 0%0%0%

A. 20% decrease

B. 25% decrease

C. 20% increase

D. 25% increase

What is the percent of change from 24 to 30 students?

A. AB. BC. CD. D

Example 2

A B C D

0% 0%0%0%

A. 17.9% decrease

B. 21.7% decrease

C. 17.9% increase

D. 21.7% increase

John had $420 in his checking account at the beginning of May. At the beginning of June he had $345. What was the percent of increase or decrease to the nearest tenth?