Percentage Calculations and Representations

The video tutorial explains how to calculate percentage increase and decrease. It demonstrates two methods for each: finding a percentage of a number and adding or subtracting it, and adjusting the percentage directly. Examples include increasing 20 by 10% to get 22 and decreasing 70 by 30% to get 49.

What is the original percentage representation of any number?

• 200%

• 150%

• 100%

• 50%

If you want to increase a number by 10%, what is the first step in the first method?

• Multiply the number by 10

• Add 10 to the number

• Subtract 10 from the number

• Find 10% of the number

After finding 10% of a number, what should you do next in the first method?

• Subtract the result from the original number

• Add the result to the original number

• Multiply the result by 10

• Divide the result by 2

In the second method of increasing a number by 10%, what percentage do you use?

• 120%

• 110%

• 100%

• 90%

How do you express 110% in rational form?

• 110/100

• 110/10

• 1.1

• 11/10

What is the first step in calculating a 30% decrease of a number?

• Add 30% to the number

• Find 30% of the number

• Multiply the number by 30

• Divide the number by 30

After finding 30% of a number, what should you do next to decrease it?

• Add the result to the original number

• Multiply the result by 2

• Subtract the result from the original number

• Divide the result by 2

In the second method of decreasing a number by 30%, what percentage do you use?

• 70%

• 100%

• 30%

• 50%

How do you express 70% in rational form?

• 70/10

• 70/100

• 7/10

• 0.7

What is the result of decreasing 70 by 30%?

• 70

• 30

• 49

• 21