To understand where the other 4 numbers will be drawn, you will need to look back at my post on Keno the keno algorithm is taking numbers 25% randomly from each space.
game 1 80 numbers 20 drawn 25%
next game will consist of 20 drawn numbers x 25% -60 remaining X 25% , then game three things become interesting, this is where you have to think about the spaces where 25% will come from numbers repeating , numbers not drawn etc etc just think outside of the square.

As with Lotto in Keno you find what are the median and mode for the Lo -Hi numbers then you have two numbers in 50% of the draws, its a matter of using the above paragraph information to formulate your next numbers