1. Percent Increase and Decrease

2. You can use a percent to describe how much something has increased or decreased.
A percent of change describes how much a quantity has changed, expressed as a percent of the original quantity.

3. When a quantity increases, the percent of change is called a percent increase.

4. Identify the percent increase in each situation.

5. A pet frog measures 51 mm in body length while sitting
A pet frog measures 51 mm in body length while sitting. Its body length extends to 89 mm while jumping. Find the approximate percent increase in body length of the frog from sitting to jumping.

6. Percent Increase
What does it mean for a quantity to increase by 100%? Explain.
The original quantity is 100% of itself. If it increases by 100%, it adds another 100% to the original quantity, making the final quantity 200% of the original quantity. This is the same as doubling the original quantity. For example, if a quantity of 10 units were to increase by 100%, the result would be a final quantity of 20 units.

7. Percent Decrease
When a quantity decreases, the percent of change is called a percent decrease.

8. The force of gravity on the Moon is different from the force of gravity on Earth. This means that an object has a different weight on the Moon than it does on Earth. By what percent does an astronaut’s weight decrease on the Moon?

9. Percent Decrease
Every 10 years, the U.S. government takes a census, or survey, of the population. One possible result of changes in population is that the number of U.S. representatives for a state may change. Find the approximate percent decrease in the number of representatives for Michigan.

10. Percent Increase and Decrease
Draw a dot to estimate the percent of change.

11. Percent Increase and Decrease
Draw a dot to estimate the percent of change.

12. Percent Increase or Decrease
Estimate the percent of change.

13. Percent of Change How can you use a percent to represent change?
A percent represents change by comparing the amount of change to the original quantity. The amount of change is the part. The original quantity is the whole. The percent is the percent of change as an increase or decrease.

14. Percent Change worksheet
HW:
Percent Change worksheet
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