Can whole numbers be rational numbers

Use this diagram, it might help.

From the inside, whatever that layer is, it can be any of the layers outside of it.

All whole numbers can be a rational number, but not all rational numbers be a whole number.

Kind of like all squares can be rectangles, but not all rectangles can be a square.

The whole number has all the attributes of a rational number, but not all rational numbers have all of the attributes of a whole number.