LOL Brad
Curiosity and something to do while eating lunch is the only reason I did it the first time, hehehe...
Dog - more math and issues than I care to even begin to go into
However - since you aren't really concerned in this case about finding
precise values for the flow rates, there is a way I could explain that would give a close enough
rough order approximation to meet your needs that is
not that hard to understand and only involves simple math you could do by hand - or more quickly, in a spreadsheet. Let me know if your interested and when I next have the time and in the mood to write it up, I will