Year 9 Percentage Increase and Decrease Worksheet — Level 3 — Practice Set 2 — 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 3 — Practice Set 2 — Answers
Percentage change = change ÷ original amount × 100. Always divide by the original amount.
1.A price changes from $280 to $210. Find the percentage decrease.
Answer: 25%
- Change = 280 − 210 = 70
- 70 ÷ 280 × 100 = 25%
2.A price changes from $540 to $405. Find the percentage decrease.
Answer: 25%
- Change = 540 − 405 = 135
- 135 ÷ 540 × 100 = 25%
3.After a 75% increase, a price is $1015. What was the original price?
Answer: $580
- New price = 175% of the original
- Original = 1015 ÷ 1.75
- = $580
4.A price changes from $180 to $189. Find the percentage increase.
Answer: 5%
- Change = 189 − 180 = 9
- 9 ÷ 180 × 100 = 5%
5.A price changes from $360 to $342. Find the percentage decrease.
Answer: 5%
- Change = 360 − 342 = 18
- 18 ÷ 360 × 100 = 5%
6.After a 5% increase, a price is $399. What was the original price?
Answer: $380
- New price = 105% of the original
- Original = 399 ÷ 1.05
- = $380
7.A price changes from $360 to $504. Find the percentage increase.
Answer: 40%
- Change = 504 − 360 = 144
- 144 ÷ 360 × 100 = 40%
8.A price changes from $100 to $60. Find the percentage decrease.
Answer: 40%
- Change = 100 − 60 = 40
- 40 ÷ 100 × 100 = 40%
9.A price changes from $100 to $70. Find the percentage decrease.
Answer: 30%
- Change = 100 − 70 = 30
- 30 ÷ 100 × 100 = 30%
10.A price changes from $660 to $165. Find the percentage decrease.
Answer: 75%
- Change = 660 − 165 = 495
- 495 ÷ 660 × 100 = 75%
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