1. Percents
Discount

2. Discount
Discounts are always fun to get, especially if you are at the department store hoping to buy some clothes for cheaper than the ticket price. In order to calculate discount, we will use the following formula: C = P – DP C = P(1-D) Most discount questions will be in the form of a word problem. Nevertheless, you must identify these three items, plug them into your formula, and solve for whatever is missing. For example…
C = total cost
P = original price
D = discount (always write as a decimal)

3. Examples
Mr. Schaffer went Christmas shopping for his three children. He bought each of them a different toy. The total amount for all three toys was $75, but Mr. Schaffer had a 20% off coupon. How much did Mr. Schaffer spend? C = P – DP C = P(1 – D) C = 75 – 75(0.2) C = 75(1 – 0.2) C = 75 – 15 C = 75(0.8) C = $60 C = $60

4. Examples
Ashley can’t wait to buy her favorite movie: Cinderella. It is on sale at Walmart for $8. If the discount Ashley will receive on the movie is 40%, what is the original cost of the movie? C = P – DP C = P(1 – D) 8 = P – 0.40P 8 = P(1 – 0.4) 8 = 0.6P 8 = 0.6P $13.33 =P $13.33 = P

5. Examples
Jessica got a new dress for a New Year’s Eve party. The dress cost $35, but Jessica got it on sale for $ How much of a discount did Jessica receive? C = P – DP C = P(1 – D) = 35 – 35D = 35 – 35D –8.75 = –35D = -35D 0.25 = D 0.25 = D 25% = D 25% = D

6. Practice Fill in the blanks of the chart below. Original Price
Discount
Total Cost
$15.00
10%
$8.50
$6.80
15%
$40.00
$25.00 5%
$14.00
$3.50
$50.00 1%
20%
$11.00

7. Practice Fill in the blanks of the chart below. Original Price Tax
Total Cost
$15.00
10%
$13.50
$8.50
20%
$6.80
$43.48
15%
$40.00
$25.00 5%
$23.75
$14.00
75%
$3.50
$50.00 1%
$49.50
$13.75
$11.00