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Blackout Keno

This week we veer off into a topic that doesn’t seem relevant to real Keno play at first but later you will see.

Earlier in my life I was employed for some years as a Keno writer. This was back in the day when we used brushes so, yes, I am that old! Anyway some shifts, especially in November, December and January, were so slow everyone wanted what we called “e.o.s” or “early outs.”

In other words, getting off work early. While this of course cost us lost wages, it saved us a few hours of mind wasting boredom. Naturally on hopelessly slow winter nights virtually the entire crew desired an “e.o.” so we had to come up with some clever way of determining who would be lucky and who would not.

Now being clever keno writers we decided to let the game decide who the lucky workers would be. If there were 10 or less of us we would each select one of the 10 columns of eight numbers and then play “blackout.”

Blackout is played by keeping track of all the numbers called and blacking them out on your ticket. As each successive draw is called, more numbers on your ticket are blacked out, kind of like bingo.

The writer whose column of eight numbers “blacked out” first was the lucky person who got to go home early. Of course this could be extended to second finisher, third etc much like a horse race. It almost never took more than an hour (eight to 10 games), before someone had blacked out their column.

Which brings us to a wider question: How long does it take on the average to blackout the entire 80 numbers on the keno board? The answer: Far less than 20 games.

The math is quite complex but the easiest solve for the problem is to use a Monte Carlo method. Just program your computer to produce keno draws and then see how long on average it takes. It’s an hour or two programming for the average code jockey.

In practical terms for the player, if you go to a keno game and ask for a printout of the draw history for the last 20 games, you should be able to verify that all 80 numbers have come up at least once. While not impossible it is improbable that a number won’t come up at all in 20 games.

The odds are over 300-1 against it. If you ask for a 100 game history and one or more numbers haven’t come up, then it is quite possible something is wrong. The odds against this are over 3 trillion to one.

Though I probably wouldn’t play at such a game if I did I certainly wouldn’t play one of the “cold” numbers. Chances are they just aren’t there.

Well that’s it for this week. Good Luck! See you in the lounge at [email protected].


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