2026 Fermat Problem 20

Arushi wrote an integer in each cell of a 3\times 4 grid so that the sum of the numbers in each row and in each column was the same. Some of the integers that Arushi wrote are shown in the grid while the others remain hidden.

7 3 4 c -1 d

The value of c-d is

\textbf{(A)}\ -1\quad \textbf{(B)}\ 0\quad \textbf{(C)}\ 5\quad \textbf{(D)}\ 10\quad \textbf{(E)}\ 13

If there are no answer choices shown, enter a numerical answer.

Full credit to this problem is given to the CEMC, you may view all Fermat contests here.