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 $150 to $165. Find the percentage increase.
Answer: 10%
- Change = 165 − 150 = 15
- 15 ÷ 150 × 100 = 10%
2.A price changes from $180 to $144. Find the percentage decrease.
Answer: 20%
- Change = 180 − 144 = 36
- 36 ÷ 180 × 100 = 20%
3.A price changes from $330 to $165. Find the percentage decrease.
Answer: 50%
- Change = 330 − 165 = 165
- 165 ÷ 330 × 100 = 50%
4.A price changes from $200 to $240. Find the percentage increase.
Answer: 20%
- Change = 240 − 200 = 40
- 40 ÷ 200 × 100 = 20%
5.A price changes from $20 to $16. Find the percentage decrease.
Answer: 20%
- Change = 20 − 16 = 4
- 4 ÷ 20 × 100 = 20%
6.A price changes from $240 to $180. Find the percentage decrease.
Answer: 25%
- Change = 240 − 180 = 60
- 60 ÷ 240 × 100 = 25%
7.A price changes from $260 to $312. Find the percentage increase.
Answer: 20%
- Change = 312 − 260 = 52
- 52 ÷ 260 × 100 = 20%
8.A price changes from $40 to $32. Find the percentage decrease.
Answer: 20%
- Change = 40 − 32 = 8
- 8 ÷ 40 × 100 = 20%
9.A price changes from $180 to $135. Find the percentage decrease.
Answer: 25%
- Change = 180 − 135 = 45
- 45 ÷ 180 × 100 = 25%
10.A price changes from $350 to $280. Find the percentage decrease.
Answer: 20%
- Change = 350 − 280 = 70
- 70 ÷ 350 × 100 = 20%
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