The number 13 is a member of the following subsets.
(Each of these subsets has an infinite number of members.)
Real numbers
Rational numbers
Integers
Natural numbers
Positive numbers
Numbers less than 14
Numbers less than 15
Numbers less than 16
.
.
Numbers greater than 12
Numbers greater than 11
Numbers greater than 10
.
.
Multiples of 13
Multiples of 2.6
Multiples of 1.3
Multiples of 3.25
Multiples of 6.5
.
.
etc.
