[quote=@Ascendant]
Three dimensional distance formula is;

Sqrt((x2 - x1)^2 + (y2 - y1)^2 + (z2 - z1)^2)

Works better if you have the coordinates instead of having to count obviously. Also works better if a computer does it for you.
[/quote]

High school tests at desks that hide my hands has given me my fair share of putting numbers into a formula with a calculator.