Two cards are drawn from a deck of 3 identical cards numbered from 1 to 3, and the first card has to be returned to the deck before the second card is drawn. Determine the number of elements in the sample space.
Since the event is drawing two cards from the deck of three cards numbered from 1 to 3, the elements of the set representing the event
are as follows: , , , , ,
, , , . Thus, the number of elements
in the set representing the event is 9.