Right cancellation in βS andUG

Let βS be the Stone-Ĉech compactification of an infinite discrete cancellative semigroupS. The set of points in the growth βS/S at which right cancellation holds in βS is shown to be dense in βS/S. It is then deduced that these type of points also form a dense subset ofUG/G, whenG is a non-compact locally compact abelian group andUG is its uniform compactification.