Worked examples
Two examples
Example 1
The rent went up from $1,500 to $1,620. What was the percent increase?
- The change: 1,620 − 1,500 = 120.
- Divide the change by the starting amount: 120 ÷ 1,500 = 0.08. As a percent: 8%.
Answer: 8%
Example 2
A price went down from $80 to $68. What was the percent decrease?
- The change: 80 − 68 = 12.
- 12 ÷ 80 = 0.15, which is 15%. Divide by the starting amount, not the new one.
Answer: 15%
Where this is taught: Ratio, Proportion, and Percent, “Percent change”
The drill
Ten problems
This drill also has challenge problems. They use the same skill, set up the way the GED test sometimes sets up a problem, so that it looks new at first.
How many:
Type the number only; the % sign is already there. Then press Check my answers at the bottom.Write each answer on the line. The answer key, with the reasoning, is on the last page.