30% of what number of 12?

Answer

To solve the problem "30% of what number is 12?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Problem Statement**: We need to find a number \( x \) such that 30% of \( x \) equals 12.

2. **Set Up the Equation**: We can express 30% as a fraction:
\[ 30\% = \frac{30}{100} \]
Thus, we can write the equation as:
\[ \frac{30}{100} \times x = 12 \]

3. **Simplify the Fraction**: The fraction \( \frac{30}{100} \) can be simplified:
\[ \frac{30}{100} = \frac{3}{10} \]
So the equation now becomes:
\[ \frac{3}{10} \times x = 12 \]

4. **Isolate \( x \)**: To find \( x \), we can multiply both sides of the equation by the reciprocal of \( \frac{3}{10} \), which is \( \frac{10}{3} \):
\[ x = 12 \times \frac{10}{3} \]

5. **Calculate \( x \)**: Now, perform the multiplication:
\[ x = \frac{120}{3} = 40 \]

6. **Conclusion**: Therefore, the number we are looking for is:
\[ x = 40 \]

### Final Answer:
30% of 40 is 12.

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