What if the floor is not exactly a foot like my floor is 11 feet 5 1/2 inches wide 11 feet 11/2 inches long

Eco Soft tiles are made of EVA foam that is easy to cut with a utility knife (or even a pair of scissors) to fit whatever area you are installing them in. If you need to make cuts to the tiles it is easiest to use a straight edge or yard stick to mark and cut straight lines and then install them.