# Determining the value of something.

``The flow is a number that varies.``

I would like to determine the value of the flow of water in the tub by what’s going on in the game.

Such that:

Flow = 2*(number of water knobs turned on) /2 if the shower knob is turned on.
Such that you can turn on the hot and cold water for a flow of 4, or only 2 if the shower knob is turned on.

We then compare the flow to the drain (which is the amount of water that leaves via the drain).

The drain is easy, because the tub drain is either clogged or not clogged. If clogged, the drain is 0, if not clogged, the drain is 3.

The purpose is to create a scenario where you can fill up the tub, without fear of over-filling, and leave the tub unattended. (So you have to clog the drain). The “red herring” is trying to fill the tub with all the water on, but when it overflows the neighbors are alerted who turn it off, or if you turn off the tub it will drain again.

Anyway, my question is, how do i determine the flow of the water in game?

Can I say something like “To decide the flow:”
or do i need “after switching on the hot water knob” and “after switching off the hot water knob”?

For values that are always determined by a formula it’s best to use to decide and definition phrases: “To decide which number is flow: decide on …” (Note that you shouldn’t define the number as a variable if you use a to decide phrase.)