Percentage Increase and Decrease Concepts

This video tutorial covers lesson 6.5b on increasing and decreasing numbers by percentages. It begins with an introduction to the concept that any number is 100% of itself. The tutorial then explains how to increase a number by a percentage, using the example of increasing 7 by 5%. It also covers decreasing a number by a percentage, using the example of decreasing 18 by 7.2%. Finally, a complex example is provided, demonstrating how to increase 0.95 by 250.78%. The video emphasizes converting percentages to decimals and rounding results.

What does it mean when we say a number is 100% of itself?

• It is half of its value.

• It is double its value.

• It is its complete value.

• It is zero.

If you increase a number by 10%, what is the new percentage of the original number?

• 110%

• 100%

• 90%

• 120%

How do you convert a percentage to a decimal?

• Move the decimal point one place to the left.

• Move the decimal point two places to the left.

• Move the decimal point one place to the right.

• Move the decimal point two places to the right.

What is the result of increasing 7 by 5%?

• 8

• 7.05

• 7.35

• 7.5

When decreasing a number by a percentage, what operation is primarily used?

• Multiplication

• Division

• Addition

• Subtraction

If you decrease 18 by 7.2%, what percentage of the original number do you have left?

• 92.8%

• 100%

• 85.6%

• 7.2%

What is the result of decreasing 18 by 7.2%?

• 18.00

• 16.00

• 17.50

• 16.70

In the complex example, what is the final percentage of the original number after increasing 0.95 by 250.78%?

• 100%

• 250.78%

• 350.78%

• 450.78%

What is the result of increasing 0.95 by 250.78%?

• 3.33

• 5.00

• 2.85

• 4.25

How do you round a number to the 100th place?

• Look at the second decimal place and round up if it's 5 or more.

• Look at the third decimal place and round up if it's 5 or more.

• Look at the fourth decimal place and round up if it's 5 or more.

• Look at the first decimal place and round up if it's 5 or more.