7、In the right figure, the sum of 3 numbers in each row, each column, and each diagonal line is equal, then $a+b+c+d+e+f=(\quad$ )



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【Analysis】Magic square. According to the problem: $\mathrm{e}=6 \times 2-4=8 ; \quad \mathrm{a}=9 \times 2-8=10 ; \mathrm{d}=(10+4) \div 2=7$. According to the properties of the magic square, the total sum of these 9 numbers is: $7 \times 9=63$; therefore, $\mathrm{a}+\mathrm{b}+\mathrm{c}+\mathrm{d}+\mathrm{e}+\mathrm{f}=63-6-4-9=44$.