 # The math behind true progressives

Aug 27, 2007 11:58 PM

There is one piece of information that we always know about a keno ticket, and that is the frequency of wins on all its catches.

There are three pieces of information on progressive tickets that we may or may not know. The first piece of information is the initial jackpot amount.

The second piece of information is the house win percentage. The third piece of information is the meter increment. Given any two of these, we can always determine the third.

For instance, you know the initial jackpot amount and the meter increment. You want to determine the house percentage.

Solution: Multiply the increment amount time the frequency of the jackpot and add this number to the initial jackpot. Calculate the house percentage using this figure in a straightforward manner.

Example: A \$2 8-spot with small pays as shown and an initial jackpot of \$100,000, with an increment of 10 cents per ticket.

 8-SPOT TICKET PRICE= \$2.00 0 / 8 0.00 1 / 8 0.00 2 / 8 0.00 3 / 8 0.00 4 / 8 0.00 5 / 8 15.00 6 / 8 175.00 7 / 8 1,480.00 8 / 8 100,000.00 HOUSE PC= .3196233

Multiplying 230,114.608 times \$0.10 gives you \$23,011.46. Adding this to the initial jackpot gives you \$123,011.46. Computing the house percentage using this number gives you a figure of 26.96%:

 8-SPOT TICKET PRICE= \$2.00 0 / 8 0.00 1 / 8 0.00 2 / 8 0.00 3 / 8 0.00 4 / 8 0.00 5 / 8 15.00 6 / 8 175.00 7 / 8 1,480.00 8 / 8 123,011.50 HOUSE PC= .2696233

Alternate solution: Calculate the house percentage with the same pay outs and with the same initial jackpot, but subtract the amount of the meter increment from the price of the ticket. This will give you the first component of the true percentage. The second component is a ticket with a price equal to the meter increment and a house percentage of zero. To calculate the true house percentage, add together the two components in ratio to their prices.

Example: Calculate the initial house percentage as above but use \$1.90 as the price of the ticket. This will result in a figure of 28.38%:

 8-SPOT TICKET PRICE= \$1.90 0 / 8 0.00 1 / 8 0.00 2 / 8 0.00 3 / 8 0.00 4 / 8 0.00 5 / 8 15.00 6 / 8 175.00 7 / 8 1,480.00 8 / 8 100,000.00 HOUSE PC= .283814

Combine the two components in ratio to their prices:

 1.90 .10 x 28.38 + x 0.0 = 26.96 2.00 2.00

Which is equal to the result from the first method.

If you have a Keno question that you would like answered, please write to me care of this paper, or contact me on the web via email at [email protected] Well, that’s i