Spark Plug:

Choose one of yourvocabulary words from Unit 3 and write as many

adjectives as you can think of that describes that word.

(must have at least 3)

Sales tax and discount

• Sales tax - is an additional amount of money charged on items people buy. The total cost is the regular price plus the sales tax.

• Discount – the amount by which the regular price of an item is reduced. The sale price is the regular price minus the discount.

Steps to finding an additional amount or discounted amount of an item:

1. Change the percent to a decimal (remove % sign and move decimal 2 places left)

2. Multiply new decimal by the item.3. If it is an “additional amount”, add

the product in step 2 to the item. If it is a “discounted amount”, subtract the product in step 2 from the item.

3. a. There is a discount of 25% off on a $60 pair of shoes. How much are the shoes?

$45

d. Why is forty-five dollars correct?

$60x .25300

120$15.00

$60- 15$45

4. a. A shirt cost $30 plus 7% tax. What is the total cost?

$32.10

d. Why is thirty-two dollars and ten cents correct?

$30x .07

$2.10

$30.00+ 2.10$32.10

5. a. A $300 bike is on sale. How much is the cost?

$225

d. Why is two hundred twenty-five dollars correct?

$300x .25150060

$75.00

$300- 75

$225

The entrance fee at an amusement park is $35. People over the age of 65 receive a 20% discount. What is the amount of the discount? How much do people over 65 pay?

Method 1 A discount is a percent decrease. So find $35 decreased by 20%.

0.20(35) = 7 Find 20% of 35. This is the amount of the discount.

35 – 7 = 28 Subtract 7 from 35. This is the entrance fee for people over the age of 65.

Method 2 Subtract the percent discount from 100%.

100% – 20% = 80% People over the age of 65 pay 80% of the regular price, $35.

0.80(35) = 28 Find 80% of 35. This is the entrance fee for people over the age of 65.

35 – 28 = 7 Subtract 28 from 35. This is the amount of the discount.

By either method, the discount is $7. People over the age of 65 pay $28.00.

A student paid $31.20 for art supplies that normally cost $52.00. Find the percent discount .

$52.00 – $31.20 = $20.80Think: 20.80 is what

percent of 52.00? Let x represent the percent.

The discount is 40%

A $220 bicycle was on sale for 60% off. Find the sale price.

Method 2 Subtract the percent discount from 100%.

100% – 60% = 40% The bicycle was 60% off of 100% .

0.40(220) = 88 Find 40% of 220. This is the discount from the original price. 220 – 88 = 142

By this method, the discount is $88. The sale price is $142.00.

Ray paid $12 for a $15 T-shirt. What was the percent discount ?

$15 – $12 = $3Think: 3 is what percent of

15? Let x represent the percent.

The discount is 20%.

The wholesale cost of a DVD is $7. The markup is 85%. What is the amount of the markup? What is the selling price?

Method 1A markup is a percent increase. So find $7 increased by 85%.0.85(7) = 5.95

7 + 5.95 = 12.95

Find 85% of 7. This is the amount of the markup.

Add to 7. This is the selling price.

Subtract from 12.95. This is the amount of the markup.

12.95 7 = 5.95

By either method, the amount of the markup is $5.95. The selling price is $12.95.

Method 2

Add percent markup to 100%

The selling price is 185% of the wholesale price, 7.

100% + 85% = 185%

Find 185% of 7. This is the selling price.

1.85(7) = 12.95

A video game has a 70% markup. The wholesale cost is $9. What is the selling price?

Method 1

A markup is a percent increase. So find $9 increased by 70%.

0.70(9) = 6.30Find 70% of 9. This is the amount

of the markup.

9 + 6.30 = 15.30 Add to 9. This is the selling price.

The amount of the markup is $6.30. The selling price is $15.30.

What is the percent markup on a car selling for $21,850 that had a wholesale cost of $9500?

21,850 – 9,500 = 12,350

The markup was 130 percent.

Think: 12,350 is what percent of 9,500? Let x represent the percent.

Remember how to