posted by Tom on .
Four players are playing a game involving choosing positions on a grid of size 3×8. Each player chooses a random position on the grid, then all players reveal their choices and a token is placed on each of the positions.
The probability that the tokens form the vertices of a non-degenerate rectangle can be expressed as a/b where a and b are coprime positive integers. What is the value of a+b?
-Players are allowed to have selected the same squares.
-There is no restriction on their choices.
-A degenerate rectangle has 0 area.
-Squares are rectangles.