Question

A computer is printing out subsets of a 3 element set (possibly including the empty set). (a) At least how many sets must be printed to be sure of having at least 4 identical subsets on the list?

Answer 1

25

Step-by-step explanation:

There are 8 different subsets, so each can be printed 3 times without ever having 4 identical subsets on the list. One more subset than those 24 will ensure that the list has at least one instance of 4 identical subset.

At least 25 sets must be printed.