This looks familiar

In the given figure, let $ABDE$ be a square, with $\angle DEC = \angle EDC = 15^{\circ}$ . Find $\dfrac{CB}{EC}$ .

Let it be of the form $\sqrt{a+\sqrt{b}}$ , where $a,b$ are square free positive integers. Enter $(a+b)$ as your answer.

For a tougher combinatorics problem, see this