Calculating Percent Increases and Taxes

The video tutorial explains how to use multiplication to calculate percent increases. It begins with an introduction to the concept, followed by a review of converting percentages to decimals and using multiplication to find percentages of numbers. Common mistakes in understanding percent increases are addressed. The tutorial provides an example of calculating the total cost of an item with a 5% sales tax. Finally, it demonstrates how to write expressions for a 12% increase over an original cost, both as a sum and a product.

What is the first step in using multiplication to find a percent increase?

• Multiply the percent by 100

• Convert the percent to a decimal

• Add the percent to the original amount

• Convert the percent to a fraction

How can 20% be expressed as a decimal?

• 20.0

• 0.02

• 0.2

• 2.0

What is a common mistake when calculating percent increase?

• Using the wrong original amount

• Multiplying instead of adding

• Forgetting to convert percent to decimal

• Thinking the percent increase is the total amount

What is the correct way to think about the total amount paid after a percent increase?

• It is the percent increase minus the original amount

• It is the original amount minus the percent increase

• It is the original amount plus the percent increase

• It is the percent increase

If an item costs $d and the sales tax is 5%, what is the expression for the total cost?

• d + 5d

• d + 0.005d

• d + 0.5d

• d + 0.05d

In the expression 1.05d, what does the '1' represent?

• The percent increase

• The sales tax

• The original cost

• The total cost

What is the final expression for the total cost of an item with a 5% sales tax?

• 1.5d

• d + 5d

• d + 0.5d

• 1.05d

How do you express a 12% increase over an original cost x as a product?

• 1.12x

• x * 0.12

• x + 12x

• x + 0.12x

What does the term '0.12x' represent in the expression for a 12% increase?

• The sales tax

• The original cost

• The total cost

• The percent increase

Which of the following is NOT a correct way to express a 12% increase over x?

• x * 1.12

• x + 0.12x

• 1.12x

• x + 12x