Subject: Math question

My name is Katie. I'm in the 7th grade, taking Algebra. I live in Houston, Texas. My problem is this:

"Use the numbers 1-9 to fill in the boxes so that you get the same sum when you add vertically, horizontally or diagonally."

The boxes are formed like a tic-tac-toe -- with 9 boxes -- 3 rows and 3 columns.

Can you help?


  Dear Katie
You might 1st try adding the numbers from 1 to 9 to get 45. If you think of the finished product it will have 3 rows of numbers and the total of the 3 rows will be 45. So each row will have a total of 15.
    If you make 9 squares of paper (with the numbers 1 to 9) you can then set out possibilities for the 3 rows so that each row has a total of 15. Then you can start looking at the 3 columns. They likely won't all have a sum of 15. If a column has a sum larger than 15 then you have to move a piece of paper to a column with a lower sum without changing rows (because you already have the rows OK). After you get the rows and columns right then you can check the 2 diagonal sums.
    You should look carefully at the middle number when you are finished and see where it lies in the list of numbers from 1 to 9. It will give you a clue as to how to do such a problem in the future because if you can predict the middle number you've got a great start towards solving your problem. You might like to look in your math book or other math books or the internet for some information on Magic Squares because that is what you have produced.


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