CEMC Pascal, 2006

Algebra Difficulty 2.0 Junior Find the answer Canada

In each row of the table, the sum of the first two numbers equals the third number. Also, in each column of the table, the sum of the first two numbers equals the third number. The table is: $\begin{array}{|c|c|c|}\hline m & 4 & m+4 \\ \hline 8 & n & 8+n \\ \hline m+8 & 4+n & 6 \\ \hline \end{array}$ What is the sum of the nine numbers in the table?

(A) $18$ (B) $42$ (C) $-18$ (D) $-6$ (E) $24$

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