I know how the mil dot is calculated at a zero, but how do you calculate multiple powers into this formula? My assumption is like this:

Lets say you have a 10 inch (or what you believe is 10 inches) prairie dog. At a single power he measures at 2.5mils. so the formula would go -

10 inches/36=2.77,

2.77x1000=277.77,

then 277.77/2.5= 111 yards away.

So when you are magnified to a 4x, how does the math go? would you divide your whole equation by 4 like so?

10/36=2.77

2.77x1000=277.77

277.77/4=69.44

2.5/4=.625

69.44/.625=111 yards

If your base zero is 100 yards on a 2x magnification, and you switch to 4x, would you only divide by 1/2?

If anyone has ANY insight on this, please fill me in.