There is a grid of 20 squares by 10 squares. How many different rectangles are possible?
(Note that square is a rectangle).

(In reply to My answer by Cindy)

20 x 20 should give 44100 by the formula n(n+1)m(m+1)/4 (see previous comments) with n=m=20, so you missed one. The problem statement is for 20 x 10, however, so the answer to the problem as stated is 11550.

Posted by Richard on 2004-01-22 16:59:17