Final answer:
To find a complex fraction that, when multiplied by 12/12, has a denominator of 1, use the fraction 12/12.
Step-by-step explanation:
To find a complex fraction that, when multiplied by 12/12, has a denominator of 1, we need to find a fraction with the numerator equal to 12 and the denominator equal to 12.
One example of such a complex fraction is 12/12. This fraction has a numerator of 12 and a denominator of 12, so when multiplied by 12/12, the denominator becomes 1.
Therefore, the complex fraction 12/12, when multiplied by 12/12, has a denominator of 1.