Final answer:
The cardinality of set S, consisting of words that can be made from letters in set A and are shorter than 6 letters, is 9.
Step-by-step explanation:
The cardinality of set S, denoted as |S|, represents the number of elements in set S. In this case, set S consists of all words that can be made from letters in set A and are shorter than 6 letters. Set A is given as {2, 4, 6, 8, 10, 12, 14, 16, 18}. To calculate the cardinality of set S, we need to count the number of words that can be formed using the letters in set A with a length less than 6.
Let's consider each letter in set A and count the number of words that can be formed using that letter alone. For example, the letter '2' can form 1 word, the letter '4' can form 1 word, and so on. Summing up the counts for each letter, we get a total of 9 words.
Therefore, the cardinality of set S is 9, i.e., |S| = 9.