To solve this, let's break the problem into steps:

1. Given information:

   • $A \%$ of $B = C$
     This implies: $\frac{A}{100} \cdot B = C$

2. Find $C$ as a percentage of $AB$:
   We need to calculate: $\text{Percentage} = \frac{C}{AB} \cdot 100$

3. Substitute $C = \frac{A}{100} \cdot B$ into the percentage formula: $\text{Percentage} = \frac{\frac{A}{100} \cdot B}{AB} \cdot 100$

4. Simplify the expression: $\text{Percentage} = \frac{A \cdot B}{100 \cdot AB} \cdot 100$ $\text{Percentage} = \frac{A}{100} \cdot 100$ $\text{Percentage} = A$

Final Answer:

If $A \%$ of $B = C$, then $C$ is $A \%$ of $AB$.

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Would you like more examples or further details?
Here are 5 related questions to deepen your understanding:

1. What is 20% of 30, and how does it compare as a percentage of $20 \times 30$?
2. If $C$ is 50% of $B$, what percentage of $AB$ is $C$?
3. How does the formula change if $A$, $B$, or $C$ are negative values?
4. Can you prove this relation graphically using examples?
5. How does this concept apply in real-world scenarios like profit or loss percentages?

Tip: Always double-check formulas by plugging in simple numbers to verify results intuitively.