Percentage Changes and Calculations

This video tutorial covers the concepts of percent increase and decrease through various examples and exercises. It begins with an introduction to the topic, followed by exercises involving rings, trading cards, sales discounts, calorie intake, investment values, badges, cat populations, and math scores. Each section provides a practical application of calculating percent changes, helping students understand the mathematical relationships and real-world implications.

If Cassandra has 5 rings, what percentage does each ring represent of the total collection?

• 20%

• 10%

• 25%

• 50%

Cassandra's aunt gives her one more ring. What is the new percentage increase in her collection?

• 25%

• 20%

• 10%

• 15%

John increased his card collection from 15 to 20 cards. What is the percentage increase?

• 50%

• 33.3%

• 25%

• 20%

Why is it useful to represent changes as percentages?

• It is a standard practice.

• It is easier to remember.

• It helps compare changes relative to the whole.

• It simplifies calculations.

A salesperson offers a 10% discount on a bill. What percentage of the original bill do you pay?

• 95%

• 80%

• 85%

• 90%

Ken reduced his calorie intake from 2500 to 2200 calories. Did he reduce by more than 7%?

• Cannot be determined

• Exactly 7%

• No

• Yes

Skylar's investment decreased by 10%. If the original amount was $75, what is the new value?

• $70.00

• $75.00

• $67.50

• $72.50

Justin earned 2 more badges, increasing his total from 8 to 10. What is the percentage increase?

• 40%

• 30%

• 25%

• 20%

If a cat population decreased by 30% and now there are 12 cats, how many were there originally?

• 15

• 20

• 17

• 18

Lou's test score increased by 25% from sixth to seventh grade, reaching 650. What was her sixth-grade score?

• 540

• 600

• 520

• 500