Place the numbers 1 to 9 into the 3x3 square so that:
(a) the sum of the three numbers in the top row is 11;
(b) the sum of the three numbers in the bottom row is 18;
(c) the sum of the three numbers in the left column is 21; and
(d) the sum of the three numbers in the right column is 17;



Please send in your answers using the letters below.
Use the format:
A =
B =
etc.

 

Solution to the Problem:

A = 6
B = 2
C = 3
D = 7
E = 4
F = 5
G = 8
H = 1
I = 9

We are given the following:
A + B + C = 11
G + H + I = 18
C + F + I = 17
A + D + G = 21

From the clues above, observe that:
There are only five possibilities for A, B, and C:
    (6,3,2), (6,4,1), (5,4,2), (8,2,1), and (7,3,1)
There are only three possibilities for A, D, and G:
    (9,8,4), (8,7,6), and (9,7,5)
Therefore, A cannot be 1, 2, 3, or 9 since they are not in the intersections of the two sets above.
I tried A = 4, but the numbers did not work.
Then I tried A = 5 and again the numbers did not work.
When I tried A = 6, I found a solution.

Correctly solved by:

1. K. Sengupta Calcutta, INDIA
2. John Funk Ventura, California
3. Scott Woody Mountain View High School
Mountain View, Wyoming
4. David & Judy Dixon Bennettsville, South Carolina
5. Russell Baker Mountain View High School
Mountain View, Wyoming
6. Hailey Granger Mountain View High School
Mountain View, Wyoming
7. Landyn Pfeifer Mountain View High School
Mountain View, Wyoming
8. Presley Gibbs Mountain View High School
Mountain View, Wyoming
9. Heather Kwolek John Handley High School
Winchester, Virginia
10. Josey Pitts Mountain View High School
Mountain View, Wyoming
11. Meagan Leonard John Handley High School
Winchester, Virginia
12. Sydney Vance John Handley High School
Winchester, Virginia
13. Les Walker Ventura, California
14. Megan Martin ----------
15. Tom Robb John Handley High School
Winchester, Virginia
16. John Crocket John Handley High School
Winchester, Virginia
17. Richard Johnson La Jolla, California