Percentage Increase + Decrease worksheet - Free Printable

Problem Analysis:

The task involves understanding percentage increases and decreases, as well as how to calculate them using multiplication factors. Let's solve each part step by step.

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1. To FIND 50% you can multiply by _______

- Explanation: Finding 50% of a number is the same as multiplying by \( \frac{50}{100} = 0.5 \).
- Answer: 0.5

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2. To FIND 25% you can multiply by _______

- Explanation: Finding 25% of a number is the same as multiplying by \( \frac{25}{100} = 0.25 \).
- Answer: 0.25

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3. To FIND 12% you can multiply by _______

- Explanation: Finding 12% of a number is the same as multiplying by \( \frac{12}{100} = 0.12 \).
- Answer: 0.12

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4. To INCREASE by 50%, you can multiply by _______

- Explanation: Increasing a number by 50% means adding 50% of the number to itself. This is equivalent to multiplying by \( 1 + 0.5 = 1.5 \).
- Answer: 1.5

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5. To INCREASE by 90%, you can multiply by _______

- Explanation: Increasing a number by 90% means adding 90% of the number to itself. This is equivalent to multiplying by \( 1 + 0.9 = 1.9 \).
- Answer: 1.9

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6. To INCREASE by 5%, you can multiply by _______

- Explanation: Increasing a number by 5% means adding 5% of the number to itself. This is equivalent to multiplying by \( 1 + 0.05 = 1.05 \).
- Answer: 1.05

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7. To INCREASE by 12%, you can multiply by _______

- Explanation: Increasing a number by 12% means adding 12% of the number to itself. This is equivalent to multiplying by \( 1 + 0.12 = 1.12 \).
- Answer: 1.12

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8. When you DECREASE by 20%, _______% remains.

- Explanation: Decreasing a number by 20% means subtracting 20% of the number from itself. The remaining percentage is \( 100\% - 20\% = 80\% \).
- Answer: 80

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9. When you DECREASE by 10%, _______% remains.

- Explanation: Decreasing a number by 10% means subtracting 10% of the number from itself. The remaining percentage is \( 100\% - 10\% = 90\% \).
- Answer: 90

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10. When you DECREASE by 25%, _______% remains.

- Explanation: Decreasing a number by 25% means subtracting 25% of the number from itself. The remaining percentage is \( 100\% - 25\% = 75\% \).
- Answer: 75

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11. When you DECREASE by 18%, _______% remains.

- Explanation: Decreasing a number by 18% means subtracting 18% of the number from itself. The remaining percentage is \( 100\% - 18\% = 82\% \).
- Answer: 82

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12. DECREASING by 20% is the same as finding 80%, so you can multiply by _______

- Explanation: Decreasing by 20% leaves 80% of the original amount. To find 80%, you multiply by \( \frac{80}{100} = 0.8 \).
- Answer: 0.8

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13. DECREASING by 40% is the same as finding _______% , so you can multiply by _______

- Explanation: Decreasing by 40% leaves 60% of the original amount. To find 60%, you multiply by \( \frac{60}{100} = 0.6 \).
- Answer: 60, 0.6

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14. DECREASING by 5% is the same as finding _______% , so you can multiply by _______

- Explanation: Decreasing by 5% leaves 95% of the original amount. To find 95%, you multiply by \( \frac{95}{100} = 0.95 \).
- Answer: 95, 0.95

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15. Is a DISCOUNT percentage increase or decrease?

- Explanation: A discount reduces the price of an item, which is a percentage decrease.
- Answer: Decrease

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16. Is a MARK UP percentage increase or decrease?

- Explanation: A markup increases the price of an item, which is a percentage increase.
- Answer: Increase

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Final Answers:

1. 0.5
2. 0.25
3. 0.12
4. 1.5
5. 1.9
6. 1.05
7. 1.12
8. 80
9. 90
10. 75
11. 82
12. 0.8
13. 60, 0.6
14. 95, 0.95
15. Decrease
16. Increase

Boxed Final Answer:

\[
\boxed{
\begin{array}{l}
1. \, 0.5 \\
2. \, 0.25 \\
3. \, 0.12 \\
4. \, 1.5 \\
5. \, 1.9 \\
6. \, 1.05 \\
7. \, 1.12 \\
8. \, 80 \\
9. \, 90 \\
10. \, 75 \\
11. \, 82 \\
12. \, 0.8 \\
13. \, 60, \, 0.6 \\
14. \, 95, \, 0.95 \\
15. \, \text{Decrease} \\
16. \, \text{Increase}
\end{array}
}
\]