Correct. The number $\displaystyle\sqrt{{{16}}}\usepackage{cmbright}\Huge\$ is the same as 4, so it belongs to both the whole number and rational number sets. 1,000,000 belongs in these two sets as well. $\displaystyle\pi\usepackage{cmbright}\Huge\$ is irrational because it is non-repeating and non-terminating; the rational quantities 3.14 and $\displaystyle\frac{{22}}{{7}}\usepackage{cmbright}\Huge\$ are only approximations of $\displaystyle\pi\usepackage{cmbright}\Huge\$ , not its actual value.