1. Percent of Increase and Decrease
Goal:
I can find percent increase and decrease.

2. Vocabulary Percent Change
A percent change is an increase or decrease given as a percent of the original amount.
A percent increase describes an amount that has grown. A percent decrease describes an amount that has been reduced.

3. Percent Change Percent change = amount of increase or decrease
original amount
This is expressed as a percentage! So you will
have to be careful with decimals!

4. Find each percent change
Find each percent change. Tell whether is a percent increase or decrease.
From 25 to 49
Percent change = amount of increase or decrease
original amount
Percent change = 25
Percent change = 0.96 = 96%. This is a percent increase, why?

5. Find each percent change
Find each percent change. Tell whether is a percent increase or decrease.
From 50 to 45
Percent change = amount of increase or decrease
original amount
Percent change = 50
Percent change = 0.10 = 10%. This is a percent decrease, why?

6. YOUR TURN: Find each percent change
YOUR TURN: Find each percent change. Tell whether is a percent increase or decrease.
1. From 200 to 110
2. From 25 to 30
3. From 80 to 115

7. Finding the result of a Percent Increase of Decrease
Find the result when 30 is increased by 20%
0.20(30) = 6
= 36
Find the result when 65 is decreased by 80%
0.80(65) = 52
65 – 52 = 13

8. YOUR TURN
1. Find the result when 72 is increased by 25%
2. Find the result when 10 is decreased by 40%

9. Vocabulary Discount Markup
A discount is an amount by which an original priced is reduced. Discount is a % of the original price. Final price = original price – discount.
Markup
A markup is an amount by which an original priced is increased. Markup is a % of the original price. Final price = original price + markup.

10. Discounts – two methods
Admission to the museum is $8. Students receive a 15% Discount. How much is the discount? How much do students pay?
Method 1 – Discount is a percent decrease.
0.15(8) = 1.20
8 – 1.20 = 6.80
Method 2 – Subtract percent discount from 100%.
100% - 15% = 85%
0.85(8) = 6.80
8 – 6.8 = 1.20

11. Christo used a coupon and paid $7
Christo used a coupon and paid $7.30 for a pizza that normally costs $ Find the percent discount.
$ $7.35 = $3.15
$3.15 = x(10.50)
0.3 = x
The discount is 30%

12. YOUR TURN
1. A $220 bicycle was on sale for 60% off. Find the sale price.
2. Ray paid $12 for a $15 T-shirt. What was the percent discount?

13. Markups – two methods
Caleb buys a necklaces at a wholesale cost of $48 each. He then marks up the price by 75% and sells them. What is the amount of the markup? What is the selling price?
Method 1 – Markup is a percent increase.
0.75(48) = 36
= 84
Method 2 – Add the markup to 100%.
100% + 75% = 175%
1.75(48) = 84
84 – 48 = 36

14. Lars purchased a daily planner for $32. The wholesale cost was $25
Lars purchased a daily planner for $32. The wholesale cost was $25. What was the percent markup?
32 – 5 =27
7 = x(25)
0.28 = x
The discount is 28%

15. YOUR TURN
1. A video game has a 70% markup. The wholesale cost is $9. What is the selling price?
2. What is the percent markup on a car selling for $21,850 that had a wholesale price of $9500?

16. Review Stuff
How do I find percent of change?
What is the difference between a markup and a discount?

17. Homework
Turn in your Homework!!!!