# Bull's-eye!

Probability Level 4

As per British Darts Organisation (BDO), the standard dart board used in international competitions has an overall diameter of $45.1\text{ cm}$, and an inner bull's-eye (red circle in the center) diameter of $12.7\text{ mm}$.

Assuming that all shots fall within the dart board area, what is the expected number of attempts needed for the player to hit the inner bull's-eye area once?