How many elements are in the set {whole numbers between 3 and 15}?
11
12
13

Whole numbers between 3 and 15 are given by:

{4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14}

Therefore, to answer the question, what we must do is to count the number of whole numbers that we have inside the set.

We note that, without including number 3 and including number 15, the number of integers is equal to 11.

There are 11 elements in the set of whole numbers between 3 and 15.