Math worksheet for calculating percentage increase or decrease between two values.

Let's solve each problem step by step.

We are asked to calculate the percentage increase or decrease from an original amount to a new amount.

Formula:

$$
\text{Percentage Change} = \left( \frac{\text{New Amount} - \text{Original Amount}}{\text{Original Amount}} \right) \times 100\%
$$

- If the result is positive, it's a percentage increase.
- If the result is negative, it's a percentage decrease.

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Let’s go through each row:

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1. Original: 990 → New: 396

Change: $ 396 - 990 = -594 $ (decrease)
$$
\frac{-594}{990} \times 100\% = -0.6 \times 100\% = -60\%
$$
✔ 60% decrease

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2. Original: 830 → New: 249

Change: $ 249 - 830 = -581 $
$$
\frac{-581}{830} \times 100\% \approx -0.70 \times 100\% = -70\%
$$
✔ 70% decrease

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3. Original: 980 → New: 147

Change: $ 147 - 980 = -833 $
$$
\frac{-833}{980} \times 100\% \approx -0.8499 \times 100\% \approx -85\%
$$
✔ 85% decrease

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4. Original: 165 → New: 33

Change: $ 33 - 165 = -132 $
$$
\frac{-132}{165} \times 100\% = -0.8 \times 100\% = -80\%
$$
✔ 80% decrease

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5. Original: 640 → New: 512

Change: $ 512 - 640 = -128 $
$$
\frac{-128}{640} \times 100\% = -0.2 \times 100\% = -20\%
$$
✔ 20% decrease

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6. Original: 520 → New: 598

Change: $ 598 - 520 = 78 $ (increase)
$$
\frac{78}{520} \times 100\% = 0.15 \times 100\% = 15\%
$$
✔ 15% increase

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7. Original: 520 → New: 546

Change: $ 546 - 520 = 26 $
$$
\frac{26}{520} \times 100\% = 0.05 \times 100\% = 5\%
$$
✔ 5% increase

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8. Original: 930 → New: 1023

Change: $ 1023 - 930 = 93 $
$$
\frac{93}{930} \times 100\% = 0.1 \times 100\% = 10\%
$$
✔ 10% increase

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9. Original: 940 → New: 1551

Change: $ 1551 - 940 = 611 $
$$
\frac{611}{940} \times 100\% \approx 0.65 \times 100\% = 65\%
$$
✔ 65% increase

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10. Original: 286 → New: 429

Change: $ 429 - 286 = 143 $
$$
\frac{143}{286} \times 100\% = 0.5 \times 100\% = 50\%
$$
✔ 50% increase

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Final Answers Table:

| Original | New | Increase/Decrease | Percentage Change |
|--------|-----|-------------------|--------------------|
| 990 → 396 | ↓ | 60% decrease |
| 830 → 249 | ↓ | 70% decrease |
| 980 → 147 | ↓ | 85% decrease |
| 165 → 33 | ↓ | 80% decrease |
| 640 → 512 | ↓ | 20% decrease |
| 520 → 598 | ↑ | 15% increase |
| 520 → 546 | ↑ | 5% increase |
| 930 → 1023 | ↑ | 10% increase |
| 940 → 1551 | ↑ | 65% increase |
| 286 → 429 | ↑ | 50% increase |

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✔ All calculations are complete and accurate.

Let me know if you'd like this formatted as a printable table!