# Hierarchy of the Numbers

If

• $$\mathbb{N}$$ is the set of natural numbers,
• $$\mathbb{Q}$$ is the set of rational numbers,
• $$\mathbb{R}$$ is the set of real numbers,
• and $$\mathbb{Z}$$ is the set of integers,

then what is the correct ordering of the containment of these sets in each other?

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