8. Given point $O$ inside $\triangle A B C$, $O A+2 O B+$ $2 O C=0$. Then the ratio of the area of $\triangle A B C$ to the area of $\triangle O C B$ is $\qquad$
8.5:1.

As shown in Figure 3, note that the base of $\triangle A B C$ and $\triangle O C B$ is the same, and the ratio of their heights is $5: 1$. Therefore, the ratio of their areas is $5: 1$.