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Let's solve each of the missing number percent problems step by step.

We are given percentages and a result, and we need to find the original number (the whole) or the percentage value, depending on what's missing.

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🔷 General Formula:

If
> P% of X = Y,
then:
> $ \frac{P}{100} \times X = Y $

So to find:
- X (the original number):
$ X = \frac{Y \times 100}{P} $
- Y (the result):
$ Y = \frac{P}{100} \times X $

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Now let’s go through each question:

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1. ___ of 50 = 45.5

We want to find the percent such that:
> ?% of 50 = 45.5

Use:
$ \frac{?}{100} \times 50 = 45.5 $

Solve for ?:
$$
\frac{?}{100} = \frac{45.5}{50} = 0.91
\Rightarrow ? = 0.91 \times 100 = 91
$$

✔ Answer: 91%

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2. 59% of ___ = 23.6

Find the number such that 59% of it is 23.6.

Use:
$ \frac{59}{100} \times X = 23.6 $

Solve for X:
$$
X = \frac{23.6 \times 100}{59} = \frac{2360}{59} \approx 40
$$

Check: $ 0.59 \times 40 = 23.6 $ ✔

✔ Answer: 40

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3. 81% of ___ = 40.5

$ \frac{81}{100} \times X = 40.5 $

$$
X = \frac{40.5 \times 100}{81} = \frac{4050}{81} = 50
$$

Check: $ 0.81 \times 50 = 40.5 $ ✔

✔ Answer: 50

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4. 75% of ___ = 15

$ \frac{75}{100} \times X = 15 $

$$
X = \frac{15 \times 100}{75} = \frac{1500}{75} = 20
$$

Check: $ 0.75 \times 20 = 15 $ ✔

✔ Answer: 20

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5. ___ of 3 = 1.8

Find percent such that ?% of 3 = 1.8

$$
\frac{?}{100} \times 3 = 1.8 \Rightarrow \frac{?}{100} = \frac{1.8}{3} = 0.6
\Rightarrow ? = 0.6 \times 100 = 60
$$

✔ Answer: 60%

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6. 56% of ___ = 3.92

$ \frac{56}{100} \times X = 3.92 $

$$
X = \frac{3.92 \times 100}{56} = \frac{392}{56} = 7
$$

Check: $ 0.56 \times 7 = 3.92 $ ✔

✔ Answer: 7

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7. 69% of 30 = ___

Find the result:
$ \frac{69}{100} \times 30 = 0.69 \times 30 = 20.7 $

✔ Answer: 20.7

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8. 29% of ___ = 26.1

$ \frac{29}{100} \times X = 26.1 $

$$
X = \frac{26.1 \times 100}{29} = \frac{2610}{29} = 90
$$

Check: $ 0.29 \times 90 = 26.1 $ ✔

✔ Answer: 90

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9. ___ of 20 = 6.2

Find percent such that ?% of 20 = 6.2

$$
\frac{?}{100} \times 20 = 6.2 \Rightarrow \frac{?}{100} = \frac{6.2}{20} = 0.31
\Rightarrow ? = 0.31 \times 100 = 31
$$

✔ Answer: 31%

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10. 82% of 10 = ___

$ \frac{82}{100} \times 10 = 0.82 \times 10 = 8.2 $

✔ Answer: 8.2

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✔ Final Answers:

| Question | Answer |
|--------|--------|
| 1 | 91% |
| 2 | 40 |
| 3 | 50 |
| 4 | 20 |
| 5 | 60% |
| 6 | 7 |
| 7 | 20.7 |
| 8 | 90 |
| 9 | 31% |
| 10 | 8.2 |

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📌 Summary Tips:

- When you know the percent and the result, divide the result by the percent (as decimal) to get the whole.
- When you know the whole and the result, divide the result by the whole and multiply by 100 to get the percent.

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