15. The figure $A B C D E F$ is a regular hexagon. Evaluate the quotient
$$
\frac{\text { Area of hexagon } A B C D E F}{\text { Area of triangle } A C D} \text {. }
$$
15 Ans: 3 .
Let $O$ be the center of the regular hexagon. Then Area $O C D=$ Area $O A C=\frac{1}{6} \times$ Area $A B C D E F$. The result follows.