Year 9 Percentage Increase and Decrease Worksheet — Level 3 — 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 3 — Practice Set 3 — Answers
Percentage change = change ÷ original amount × 100. Always divide by the original amount.
1.After a 20% decrease, a price is $192. What was the original price?
Answer: $240
- New price = 80% of the original
- Original = 192 ÷ 0.8
- = $240
2.After a 40% decrease, a price is $300. What was the original price?
Answer: $500
- New price = 60% of the original
- Original = 300 ÷ 0.6
- = $500
3.A price changes from $200 to $160. Find the percentage decrease.
Answer: 20%
- Change = 200 − 160 = 40
- 40 ÷ 200 × 100 = 20%
4.A price changes from $760 to $874. Find the percentage increase.
Answer: 15%
- Change = 874 − 760 = 114
- 114 ÷ 760 × 100 = 15%
5.After a 5% increase, a price is $525. What was the original price?
Answer: $500
- New price = 105% of the original
- Original = 525 ÷ 1.05
- = $500
6.A price changes from $100 to $110. Find the percentage increase.
Answer: 10%
- Change = 110 − 100 = 10
- 10 ÷ 100 × 100 = 10%
7.After a 75% increase, a price is $1365. What was the original price?
Answer: $780
- New price = 175% of the original
- Original = 1365 ÷ 1.75
- = $780
8.A price changes from $640 to $768. Find the percentage increase.
Answer: 20%
- Change = 768 − 640 = 128
- 128 ÷ 640 × 100 = 20%
9.A price changes from $560 to $504. Find the percentage decrease.
Answer: 10%
- Change = 560 − 504 = 56
- 56 ÷ 560 × 100 = 10%
10.After a 5% increase, a price is $840. What was the original price?
Answer: $800
- New price = 105% of the original
- Original = 840 ÷ 1.05
- = $800
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