69. A right circular cone with vertex $S$ is inscribed in a triangular pyramid $S P Q R$ such that the circle of the cone's base is inscribed in the base $P Q R$ of the pyramid. It is known that $\widehat{P S} R=\pi / 2, \widehat{S Q R}=\pi / 4, \widehat{P S} Q=7 \pi / 12$. Find the ratio of the lateral surface area of the cone to the area of the base $P Q R$ of the pyramid.
69. $\pi \frac{4 \sqrt{3}-3}{13}$.