4. (10 points) Place the six numbers $1,3,5,7,9,11$ into the circles in the right figure (one number per circle) so that the sum of the three numbers on each side is 19. Then the sum of the three numbers in the circles at the vertices of the triangle is $\qquad$ .


4. (10 points) Place the six numbers $1,3,5,7,9,11$ into the circles in the right figure (one number per circle) so that the sum of the three numbers on each side is 19. Then the sum of the three numbers in the circles at the vertices of the triangle is $\qquad$.

【Analysis】Since the three numbers at the vertices of the triangle are added one extra time, the sum of the numbers on each side minus the sum of the numbers filled in equals the sum of the numbers at the vertices, i.e., $19 \times 3-(1+3+5+7+9+11)=21$, so the sum of the three numbers at the vertices is 21.

【Solution】Solution: $19 \times 3-(1+3+5+7+9+11)$,
$$
\begin{array}{c}
=19 \times 3-36, \\
=21 ;
\end{array}
$$

Therefore, the answer is: 21.