Trying to get an equation more so than the answer for future reference sake for dosing trace amounts of minerals or elements. Wasn't sure if it was a simple or complex thing.

It's really simple. For aqueous solutions, ppm is practically the same as milligrams per liter. So:

ppm = milligrams of solute / liters of solution

In the case of a liquid solute like your solute "A", whose volume you know, you need to convert the volume to weight. One milliliter of water weighs one gram (1000 milligrams) at standard temperature. Other liquids may weigh more or less per milliliter, but if "A" is an aqueous solution, you can safely use one gram per milliliter for its weight. If "A" is not aqueous (like alcohol, for example), you need to multiply the volume times the specific gravity.

So in your example, 0.725 milliliters of "A" in 1022 liters of water, assuming A is an aqueous solution, has a concentration of:

725 / 1022 = 0.71 ppm

If "A" were ethyl alcohol, it would have a specific gravity of 0.79. So the concentration of A would be:

(725 * 0.79) / 1022 = 0.56 ppm