Percentages and Their Applications

The video tutorial by Mrs. Apia covers lesson four on percent increase and decrease. It explains how to solve percent problems when one quantity is a certain percent more or less than another. The lesson includes examples such as Cassandra's jewelry box, Ken's calorie intake, Justin's badges, cat population, and test scores. Each example demonstrates how to calculate percent increase or decrease and find original amounts. The tutorial emphasizes the importance of identifying the whole unit in percent problems.

What is the formula used to calculate the quantity in percent problems?

• Quantity = Whole / Percent

• Quantity = Percent + Whole

• Quantity = Percent x Whole

• Quantity = Whole - Percent

If Cassandra receives an additional ring, what is the percent increase in her collection?

• 30%

• 25%

• 20%

• 10%

Ken reduced his calorie intake from 2500 to 2200. Did he achieve a 7% reduction?

• Yes, but only if rounded

• No, he reduced by less than 7%

• No, he reduced by more than 7%

• Yes, he reduced by exactly 7%

What is the percent increase in Justin's badge collection if he earns two more badges?

• 20%

• 25%

• 30%

• 35%

Express 10 badges as a percent of 8 badges.

• 125%

• 120%

• 110%

• 100%

If a population of cats decreased by 30% to 12, what was the original population?

• 18

• 15

• 16

• 17

Lou's 7th-grade math score was 650, which was 25% higher than her 6th-grade score. What was her 6th-grade score?

• 500

• 540

• 520

• 560

Mary has 20% more money than John. What is the whole unit in this comparison?

• The total money they have

• The difference in their money

• John's money

• Mary's money

If Ann has 15% less money than John, what is the whole unit?

• Ann's money

• John's money

• The difference in their money

• The total money they have

What does the 'whole' represent in the percent formula?

• The change in amount

• The original amount

• The percent change

• The final amount