Hey Andrue..
Sorry..but your dosages and such are a little off..they don't make percocet in a 20 mg dose..
They make oxycontin in 20, 40 and 80 mg doses...
And it's not a joke..the shit kills people...
Heres actual info on the drug..
http://www.drugs.com/mtm/p/percocet_5_325.html