Pat will walk from intersection X to intersection Y along a route that is confind to the square grid of four streets and three avenues. (If you draw a grid, you have 4 horizontal lines and 3 vertical lines. X is on your lower left and Y is on your upper right. This problem is #195 in OG11
How many routes can Pat tale that have the min possible length?
Does anyone have a logically method of solving this problem with simply writing out all the possiblity? What is the logically basis?