The missing numbers are between 1 & 9. The three numbers in top columns, when subtracted by the lower two numbers, equals the three totals along the bottom, and the three numbers in the left rows, when subtracted by the right two numbers, equals the three totals at the far right. The top left number, when subtracted by the lower two numbers on its diagonal, equals the total in the bottom, far right box. Solve the puzzle by finding all of the missing numbers that satisfy all of the results as shown.
Letters (B, C, D, E, F, G and H) have been inserted in the original puzzle example, so that the unknown values can be determined.
The puzzle gives us 7 equations with 7 unknown values, as follows:
The equations are solved as follows:
Giving us the final solution:
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