Year 9 Percentage Increase and Decrease Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 percentages worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · PercentagesYear 9 Percentage Increase and Decrease Worksheet — Level 1 — Practice Set 3 — Answers
Percentage change = change ÷ original amount × 100. Always divide by the original amount.
1.A price changes from $240 to $180. Find the percentage decrease.
Answer: 25%
- Change = 240 − 180 = 60
- 60 ÷ 240 × 100 = 25%
2.A price changes from $120 to $150. Find the percentage increase.
Answer: 25%
- Change = 150 − 120 = 30
- 30 ÷ 120 × 100 = 25%
3.A price changes from $250 to $275. Find the percentage increase.
Answer: 10%
- Change = 275 − 250 = 25
- 25 ÷ 250 × 100 = 10%
4.A price changes from $20 to $30. Find the percentage increase.
Answer: 50%
- Change = 30 − 20 = 10
- 10 ÷ 20 × 100 = 50%
5.A price changes from $180 to $216. Find the percentage increase.
Answer: 20%
- Change = 216 − 180 = 36
- 36 ÷ 180 × 100 = 20%
6.A price changes from $230 to $207. Find the percentage decrease.
Answer: 10%
- Change = 230 − 207 = 23
- 23 ÷ 230 × 100 = 10%
7.A price changes from $90 to $99. Find the percentage increase.
Answer: 10%
- Change = 99 − 90 = 9
- 9 ÷ 90 × 100 = 10%
8.A price changes from $370 to $185. Find the percentage decrease.
Answer: 50%
- Change = 370 − 185 = 185
- 185 ÷ 370 × 100 = 50%
9.A price changes from $300 to $225. Find the percentage decrease.
Answer: 25%
- Change = 300 − 225 = 75
- 75 ÷ 300 × 100 = 25%
10.A price changes from $290 to $435. Find the percentage increase.
Answer: 50%
- Change = 435 − 290 = 145
- 145 ÷ 290 × 100 = 50%
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.