8.4 Percent of Change

Percent of Change

Definitions

• Percent of Change - the percent by which a number increases or decreases.

• Percent Decrease - a percent change describing a decrease in a quantity.

• Percent Increase- The percent change describing an increase in a quantity.

Percent Change

describes how much a quantity decreases or increases in relation to the original amount

for example: the percent off in this sale is the percent change

Calculating Percent Change

Multiple Choice

1. Find the PERCENT of change.

20 dogs to 5 dogs

• Decrease 15%

• Increase 15%

• Increase 75%

• Decrease 75%

Multiple Choice

2. Find the PERCENT of Change.

The original cost was $50 and the new cost is $60.

• Increase 20%

• Increase 16.67%

• Increase $10

• Decrease $10

Multiple Choice

3. Find the percent of change if Eddie started with 20 tickets and ended with 30 tickets.

• Increase 10 tickets

• Increase 50%

• Increase 33%

• Decrease 50%

Multiple Choice

4. Last week, you finished level 2 of a video game in 32 minutes. Today, you finished level 2 in 28 minutes. What is your percent of change?

• Increase 12.5%

• Decrease 12.5%

• Increase 4%

• Decrease 4%

Multiple Choice

5. Ann works in a supermarket for $10.00 per hour. She received a raise to $12.00. What is the percent of change in her hourly wage?

• Increase 16.67%

• Decrease 16.67%

• Increase 20%

• Decrease 20%

Multiple Choice

6. One week, 72 people got a speeding ticket. The next week, only 36 people got a speeding ticket. What is the percent of change in the speeding tickets?

• Increase 50%

• Decrease 50%

• Increase 1%

• Decrease 1%

Multiple Choice

8. Mrs. Boyd has 35 students in her science class.If her class increases to 42 students next year, what will be the percent of change?

• 20% decrease

• 75% increase

• 93% increase

• 33% decrease

Multiple Choice

1.) Carlos took a test and made a 50. On the next test, he made a 75. What was the percent of change between the two test scores?

• 50% increase

• 50% decrease

• 25% increase

• 25% decrease

Multiple Choice

2.) Bob got a raise, and his hourly wage increased from $12 to $15. What is the percent of change?

• 25% decrease

• 25% increase

• 20% decrease

• 20% increase

Multiple Choice

3.) The price of a pair of shoes increases from $20 to $32. What is the percent the price of the shoes changed?

• 37.5% increase

• 37.5% decrease

• 60% increase

• 60% decrease

Multiple Choice

4.) At a coffee shop, the price of a cup of coffee increased from $1.20 to $1.44. What is the percent of change in the cost of the coffee?

• 16.66% increase

• 16.66% decrease

• 20% decrease

• 20% increase

Multiple Choice

5.) In a class, the number of students has been decreased from 27 to 18. Find the percent of change.

• 33.33% decrease

• 33.33% increase

• 50% decrease

• 50% increase

Multiple Choice

6.) The price of gasoline dropped from $2.40 to $2.24 in one month. By what percent did the gas price change ?

• 6.67% increase

• 6.67% decrease

• 7.14% increase

• 7.14% decrease

Multiple Choice

8.) As soon as a new car is purchased and driven away from the dealership, it begins to lose its value, or depreciate. Alonso bought a 2004 Plymouth Neon for $9559. One year later, the value of the car was $8500. What was the percent of change of the value of the car?

• 11.08% decrease

• 11.08% increase

• 12.46% decrease

• 12.46% increase

Multiple Choice

The regular price of a scooter is $65.50. It is on sale for $52.40. What is the percent decrease from the regular price to the sale price of the scooter? 

• 35%

• 25%

• 30%

• 20%

Multiple Choice

Find the percent increase. Round to the nearest percent.
From $5 to $8 

• 40%

• 60%

• 55%

• 65%

Multiple Choice

Find each percent increase. Round to the nearest percent.
From 13 friends to 14 friends  

• 20%

• 12%

• 15%

• 8%

Multiple Choice

Mrs. Ciampa had 27 students in her class last year and this year she had 30 students in her math class. What is the percent of change?

• 24%

• 20%

• 11%

• 50%

Multiple Choice

Find each percent decrease. Round to the nearest percent.
From $80 to $64 

• 35%

• 10%

• 20%

• 25%

Multiple Choice

Tickets to Disney World are $100.The price is going to increase on January 1. What is the percent of change if the cost increases to a $120?

• 25%

• 18%

• 20%

• 50%

Multiple Choice

A baby was 16 inches long when it was born. It is now 26 inches long. What is the percent of change?

• 62.5% increase

• 26% increase

• 50% increase

• 10% increase