Originally Posted by
danielle_54321 First, I created a checkerboard on paper and wrote in each square the number of rectangles that would use that square as a bottom right corner such as this:
1 2 3 4 5 6 7 8 9 10
2 4 6 8 10 12 14 16 18 20
3 6 9 12
4 8 12 16
5 10 15 20 25
6
7
8
9
10
until I had the whole grid finished. Then I added them all up.
Also, I found an equation on the internet that is supposed find the number of rectangles in a checkerboard. (also this isncludes squares)
The formula is :
[n(n+1)/2]^2
therefore:
[10(10+1)/2]^2
=[10(11)/2]^2
=[110/2]^2
=55^2
=3025
Please, if you could help, it's really important.