The formula to calculate the Magnification (M) is:
\[ \text{M} = \frac{\text{d}_i}{\text{d}_o} \]
Where:
Let's say the image distance (di) is 20 cm and the object distance (do) is 10 cm. Using the formula:
\[ \text{M} = \frac{20}{10} = 2 \]
So, the magnification is 2, indicating the image is twice the size of the object.