Suppose U = {1, 2, 3, 4, 5, 6, 7, 8} is the universal set and P = {1, 2, 3, 4}. What is P'?

P' is the complement of set P in the universal set U. It consists of all the elements in U that are not in P.

In this case, P' would be {5, 6, 7, 8}, since these elements are in U but not in P.