[net.math] What are the odds in Keno?

jeff@heurikon.UUCP (02/15/84)

Has anyone out there computed the odds in Keno?  (Keno is a
gambling game that looks a lot like Bingo, but isn't, mainly
because you almost always loose.) I played Keno during Comdex
but didn't know the best way to play a ticket.

For those of you who don't have a Keno rule sheet handy (some
people don't carry them around all the time like I do), here
is a sample from the rules:

There are 80 different numbers.  There will be a random drawing
of 20 of these numbers.  The object is to select and bet the
numbers that will be drawn.  You may "mark" from 1 to 15 numbers.
There are payoffs in each category for "catches" greater than
or equal to about 1/2 the total spots which you marked.  However,
the maximum payoff is limited to $50,000, regardless of the odds
or the amount you bet.

	Mark Eight Spots		Mark Four Spots	
	Catch    Pays			Catch	 Pays
	  5	  x9			  2	  x1
	  6	 x92			  3	  x4
	  7	x1480			  4	 x112
	  8	x18,000
					Mark Six Spot
	Special Four Spot		Catch	 Pays
	Catch	 Pays			  3	  x1
	  3	  x5			  4	  x4
	  4	 x160			  5	 x88
					  6	x1480

There are many more ways to play a ticket, and lots of combinations.
If you're going to play, the object ought to be to select the *best*
way of playing.  So one must compute all the odds for the variations.
Anybody know how?  Or better yet, is there a general formula which
can be used to quickly calculate the odds?  The problem is complicated
because you can win in so many ways.  If you need more information,
I'll be glad to USMail you the whole set of payoff tables.

Please post your answers.  Thanks.
-- 
/"""\	Jeffrey Mattox, Heurikon Corp, Madison, WI
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