Multiplication square poster
Multiplication Square Poster
Age
11 to 14
Challenge level
Problem
This poster is based on the problem Multiplication Square.
The poster is available as a PDF, or the image below can be clicked on to enlarge it.
Student Solutions
For 2 by 2 squares, the difference between the diagonal sums is always 1
For 3 by 3 squares, the difference between the diagonal sums is always 4
For 4 by 4 squares, the difference between the diagonal sums is always 10
Why?
Say the top left corner of the square is on $a\times b$.
2 by 2 square:
Image
3 by 3 square:
Image
4 by 4 square:
Image
