# What is the distance between (22,5,7) and (21,4,0)?

$= \sqrt{51}$
We may use the distance formula for the metric space of ${\mathbb{R}}^{3}$ to find
d[(22,5,7);(21,4,0)]=sqrt((22-21)^2+(5-4)^2+(7-0)^2
$= \sqrt{51}$