Year 9 Percentage Increase and Decrease Worksheet — Level 3 — Practice Set 4 — 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 4 — Answers
Percentage change = change ÷ original amount × 100. Always divide by the original amount.
1.After a 60% increase, a price is $1248. What was the original price?
Answer: $780
- New price = 160% of the original
- Original = 1248 ÷ 1.6
- = $780
2.A price changes from $60 to $45. Find the percentage decrease.
Answer: 25%
- Change = 60 − 45 = 15
- 15 ÷ 60 × 100 = 25%
3.A price changes from $120 to $30. Find the percentage decrease.
Answer: 75%
- Change = 120 − 30 = 90
- 90 ÷ 120 × 100 = 75%
4.A price changes from $500 to $550. Find the percentage increase.
Answer: 10%
- Change = 550 − 500 = 50
- 50 ÷ 500 × 100 = 10%
5.A price changes from $320 to $352. Find the percentage increase.
Answer: 10%
- Change = 352 − 320 = 32
- 32 ÷ 320 × 100 = 10%
6.After a 40% increase, a price is $812. What was the original price?
Answer: $580
- New price = 140% of the original
- Original = 812 ÷ 1.4
- = $580
7.A price changes from $140 to $245. Find the percentage increase.
Answer: 75%
- Change = 245 − 140 = 105
- 105 ÷ 140 × 100 = 75%
8.After a 25% increase, a price is $375. What was the original price?
Answer: $300
- New price = 125% of the original
- Original = 375 ÷ 1.25
- = $300
9.After a 10% decrease, a price is $270. What was the original price?
Answer: $300
- New price = 90% of the original
- Original = 270 ÷ 0.9
- = $300
10.After a 10% increase, a price is $330. What was the original price?
Answer: $300
- New price = 110% of the original
- Original = 330 ÷ 1.1
- = $300
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