Over Lesson 7–5

A. 37.5

B. 36.705

C. 35.505

D. 34.705

Find 26.3% of 135.

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.

• percent of change - Is the ratio that compares the change in quantity to the original amount.

• percent of increase – Positive increase.

• percent of decrease – Negative decrease.

• markup – The amount of increase.

• selling price – The amount a customer pays for an item.

• discount – The amount by which the selling or regular price is reduced.

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

Simplify.

Answer: 20%; increase

Step 3 The decimal 0.20 is written as 20%. Thepercent of change is positive, so it is a percentof increase.

A. –20%; decrease

B. –25%; decrease

C. 20%; increase

D. 25%; increase

What is the percent of change from 24 to 30 students?

Find the Percent of Change

Pedro had 325 trading cards. He now has 270 trading cards. Find the percent of change. Round to the nearest tenth, if necessary. Then state whether the percent of change is an increase or decrease.

Step 1 Subtract to find the amount of change.

270 – 325 = –55 final amount – originalamount

Step 2 Write a ratio that compares the amount ofchange to the original amount. Express theratio as a percent.

Find the Percent of Change

Divide. Use a calculator.Answer: To the nearest percent, the percent of change

is –16.9%. Because the percent is negative, it is a percent of decrease.

Substitution

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?

Find the Selling Price

Find the selling price if a store pays $68 for a portable DVD player, and the markup is 35%.

Method 1 Find the amount of markup first.

The whole is $68. The percent is 35. You need to find the amount of the markup, or the part. Let m represent the amount of the markup.

Then add the markup to the cost.

So, $68 + $23.80 = $91.80.

m = 0.35 ● 68 part = percent ● whole

m = 23.80 Multiply.

Find the Selling Price

Method 2 Find the total percent first.

Use the percent equation to find 100% + 35% or 135% of the price. Let p represent the price.

p = 1.35 ● 68 part = percent ● whole

p = 91.80 Multiply.

Answer: Using either method, the selling price is $91.80

A. $28.80

B. $48.40

C. $67.20

D. $88.00

The markup on a pair of shoes is 40%. If the store paid $48 for a pair of shoes, what is the selling price?

Find the Sale Price

BASEBALL MITT CR Sporting Goods is having a sale. A baseball mitt has an original price of $89. It is on sale for 25% off the original price. Find the sale price of the baseball mitt.

Method 1 Find the amount of the discount.

The whole is $89. The percent is 25. You need to find the amount of the discount, or the part. Let d represent the amount of the discount.

Subtract the discount from the cost.

So, $89 – $22.25 = $66.75.

d = 0.25 ● 89 part = percent ● whole

d = 22.25 Multiply.

Find the Sale Price

Method 2 Find the total percent first.

Use the percent equation to find 100% – 25% or 75% of the price. Let p represent the sale price.

p = 0.75 ● 89 part = percent ● whole

p = 66.75 Multiply.

Answer: Using either method, the sale price is $66.75.

A. $11.20

B. $20.80

C. $27.00

D. $43.20

A store is having a 35% off sale. What is the sale price of a shirt normally costing $32?