Setting the Table
Fill the grid with consecutive numbers.
The sums of the rows and columns are shown.
Fill the grid with consecutive numbers.
The sums of the rows and columns are shown.
Here is a 3 x 3 table. The row sums are show at the right, the column sums at the bottom.
We have the numbers 1 2 3 4 5 6 7 8 9 to work with. 21 – 7 = _ + _. So we need two numbers that sum to 14; candidates are: 5 + 9 and 6 + 8. We’ll just guess and hope for the best.
Since 13 is the smallest row, we’ll try that next: 13 = 6 + _ + _. Candidates are: 2 + 5, 3 – 4. Guess again:
The only possibility for row 3 is: 14 = 8 – 1 + 5, but this won’t work: if you put 5 in column 3 then: 11 = 5 + 3 + 3 and if you put 1 in column 3 you get: 11 = 1 + 3 + 7. Let’s swap the 3 and 4 in row two and see what happens:
Now we try column three: 11 = 5 + 4 + 2, which works and then column one: 13 = 1 + 3 + 9, which also works.
Fortunately, the row one sum works out and the puzzle is solved. Our choice and placing of 6 and 8 at the start was lucky indeed! Is there a better strategy .. try to find one.
Have fun!