1. Do Now Write each proportion and answer.
54% of the 1,250 kids at Park Ave. have some computer restrictions at home. Determine what part of the population that is.
74% of 12 year olds use IM. Predict how many of the 2,480 middle school kids that is.

2. Chapter 8 Lesson 4 Percent of Change
Objective: Find the percent of increase or decrease

3. Percent Change
Is a ratio that compares the change in quantity to the original amount.
amount of change
original amount
Percent of change =

4. The original quantity is increased
Percent Increase
The original quantity is increased
amount of change
original amount
(New amount – original amount)
Percent of change =

5. The original quantity is decreased.
Percent Decreased
The original quantity is decreased.
amount of decrease
original amount
(Original amount – new amount)
Percent of change =

6. The percent of increase in the tree height is 140%
Find the percent of change in tree height from one year to year 10. Round to the nearest whole percent if necessary.
Percent of increase
amount of change
original amount
Percent of change =
= 5.6
5.6 4
9.6 ft
1.4
4 ft
140%
The percent of increase in the tree height is 140%

7. Find the percent of change if the original price of a stock was $75 and the new price is $60. Round to the nearest whole percent if necessary.
Percent of Decrease
Stock
Price
Original
$75
New
$60
amount of decrease
original amount
Percent of change =
75 – 60 = $15 15 75
0.2
20%

8. Original: 10 New: 13 Increase 13 -10 = 3 3 10 30%
Find each percent of change. Round to the nearest whole percent if necessary. State whether the percent of change is an increase or decrease.
Original: 10
New: 13
Increase
= 3 3 10
30%

9. decrease 20 - 15 5 20 25% Original: 20 New: 15
Find each percent of change. Round to the nearest whole percent if necessary. State whether the percent of change is an increase or decrease.
Original: 20
New: 15
decrease 5 20
25%

10. Original: 30 New: 24 decrease 30 – 24 = 6 6 30 20%
Find each percent of change. Round to the nearest whole percent if necessary. State whether the percent of change is an increase or decrease.
Original: 30
New: 24
decrease
30 – 24 = 6 6 30
20%

11. Original: $75.80 New: $94.70 Increase $94.70 – 75.80 = $18.90 18.90
Find each percent of change. Round to the nearest whole percent if necessary. State whether the percent of change is an increase or decrease.
Original: $75.80
New: $94.70
Increase
$94.70 – = $18.90
18.90
75.80
= 25%

12. Original: $126 New: $150 Increase 150 – 126 = 24 24 126 .1904 = 19%
Find each percent of change. Round to the nearest whole percent if necessary. State whether the percent of change is an increase or decrease.
Original: $126
New: $150
Increase
150 – 126 = 24 24
126
.1904 = 19%

13. Original: 1.6 New: 0.95 decrease 1.6 – 9.95 = .65 .65 1.6
Find each percent of change. Round to the nearest whole percent if necessary. State whether the percent of change is an increase or decrease.
Original: 1.6
New: 0.95
decrease
1.6 – 9.95 = .65
.65
1.6
= 41%

14. Original: 624 New: 702 Increase 702 – 624 = 78 78 624 0.125 = 13%
Find each percent of change. Round to the nearest whole percent if necessary. State whether the percent of change is an increase or decrease.
Original: 624
New: 702
Increase
702 – 624 = 78 78
624
0.125 = 13%

15. Do numbers 11-21 odd on page 352 in your textbook

16. Homework Page 352 numbers 12 – 22 even.