splash screen. then/now you have already solved real-world problems using the percent equations....
TRANSCRIPT
You have already solved real-world problems using the percent equations. (Lesson 7–5)
• Find percent of increase and decrease.
• Solve real-world problems involving markup and discount.
If the answer is positive, the percent of change is an increase.
If the answer is negative, the percent of change is a decrease.
Find the Percent 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 final amount – original amount
Step 2 Write a ratio that compares the amount ofchange to the original amount. Express theratio as a percent.
Find the Percent of Change
Cross multiply.
Answer: 20%; increase
Step 3 The percent of change is positive, so it is a percent of increase.
4 • 100 = 20 • x
20% = x Divide.
A. –20%; decrease
B. –25%; decrease
C. 20%; increase
D. 25%; increase
What is the percent of change from 24 to 30 students?
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?