To solve the equation \( \frac{x}{4} = 12 \) using the inverse operation, we need to isolate \( x \).
The inverse operation of division (which is what we have in \( \frac{x}{4} \)) is multiplication.
So we multiply both sides of the equation by 4:
\[ x = 12 \times 4 \]
Calculating the right side:
\[ x = 48 \]
Thus, the correct answer is:
Inverse operation is multiplication; x = 48.