Let O A = a, O B =12 a +4 b and O C = b, where O is the origin. If S is the parallelogram with adjacent sides OA and OC, then (area of the…

Let $\displaystyle \overrightarrow{O A}=\vec{a}, \overrightarrow{O B}=12 \vec{a}+4 \vec{b}$ and $\displaystyle \overrightarrow{O C}=\vec{b}$, where O is the origin. If S is the parallelogram with adjacent sides OA and OC , then $\displaystyle \frac{\text { area of the quadrilateral } \mathrm{OABC}}{\text { area of } \mathrm{S}}$ is equal to $\displaystyle \_\_\_\_$