The set of natural numbers less than 20 is finite: {0, 1, 2, ..., 19} has 20 elements.
The set of improper fractions is infinite.
The set of odd numbers greater than 1 and less than 100 is finite: {3, 5, 7, ..., 99} has 49 elements.
The set of improper fractions is infinite.
The set of odd numbers greater than 1 and less than 100 is finite: {3, 5, 7, ..., 99} has 49 elements.