Magic Constants
In a Magic Square all the rows, columns and diagonals add to the 'Magic Constant'. How would you change the magic constant of this square?
Problem
This is a 4 × 4 Magic Square made from the numbers 1 to 16.
In a Magic Square all the rows, columns and diagonals add to the same number. This number is called the 'Magic Constant'.
Here are some questions about this Magic Square.
1/What is the Magic Constant of this Magic Square?
This particular square is especially 'magic' as some 2 × 2 squares within it also add to that number.
2/How many of these squares can you find?
3/What happens to the Magic Constant if you add 2 to each number in the square?
4/What happens if you double each number?
5/Can you make a square in which the Magic Constant is 17?
7/What other numbers under 100 can you make into the Magic Constant by changing all the numbers in the square in the same way?
8/Can some be made in more than one way?
9/Are there some numbers you really cannot make?
Teachers' Resources
Using NRICH Tasks Richly describes ways in which teachers and learners can work with NRICH tasks in the classroom.
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