11. (5 points) In the 9 squares shown in the figure, the sum of the three numbers in each row, each column, and each diagonal is equal, then $x+y+a+b+c+d=$ $\qquad$ .

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【Analysis】First, according to the rule of magic squares where the sum of numbers on each line is equal, we can determine that $y$ is 7 by the comparison method. Then, we can set the magic sum as $22+c$ to represent it. Continue the calculation to solve the problem.

【Solution】Solution: According to the problem, we know:
$y=4+15-12=7$. The magic sum can be expressed as $15+7+c=22+c$.
So $a=10, d=18 . x=c+3, b=c-3$.
The magic sum $3+c+c+c-3=22+c$.
Solving for $c=11$, then $11+14+8+10+18+7=68$.
Therefore, the answer is: 68.