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# Ask the Slot Expert: Completing flushes on multi-hand video poker

21 September 2016

Question: I like to play Ten-Play video poker. It seems like I should get two or three flushes each time I hold a 4-card flush -- ten hands divided four suits is 2.5 hands. There are so many times that I get only one flush -- or none -- that I think my average is much lower.

Answer: It seems like you have a 1-in-4 chance of completing the flush, but that's not the case. Let's do the math.

Your hand has four cards in one suit and one card in another suit. There are 47 cards remaining in the deck. How many of the cards are in the suit you need? There are already four in your hand. That leaves nine cards of your suit left in the deck.

Your chances for completing the flush are 9-in-47 (0.19) not 1-in-4 (0.25). On the average, you'll complete the flush just under two hands each time you draw to a 4-card flush.

Question: I have a couple of questions. Of course, the answers don’t really matter since the RNG is going to land where it lands, but I am still curious.

First, if I sit down at a multi-game video machine and play dollar Double Bonus, for instance, for an hour, I am thinking that the RNG is slowly getting the odds in my favor to hit. Then, if I switch to say Double Double Bonus, does the same RNG run the outcome for that and all of the games, or is there a completely different RNG for each game on the multi-game machine? The same question applies to multi-denomination slot machines. It seems like sometimes you can do really well playing one denomination, then switch to another value and get skunked, yet switch back to the original and do well again. Makes it seem like a totally different RNG for each denomination.

Second, some machines like the Blazing Sevens and Majestic Lions progressives, I was told years ago that the RNG does its work ahead of time and that the spin combinations are selected by the RNG when the machine is built and the computer is already programmed ahead of time as to what spin results will appear so it makes no difference when you hit that spin button like it does with an active RNG on IGT machines.

Thanks in advance for your answers. I realize none of this matters, but it has always gone through my head that the split second I hit the button, the RNG stops and that is my fate for that spin, but on the Blazing Sevens, it may not matter at all when you hit the button because it already knows.

Answer: To rephrase your first question, is the RNG function part of the game program or is it part of the machine's operating system (OS)? If it's part of the OS, all game programs can use the same RNG function. If it's part of the game program, then each game program contains a separate instance of the RNG function, even though the actual instructions in the function are identical in all game programs.

Slot manufacturers do not release many technical details about how their RNGs are implemented because they don't want to help RNG cheats reverse engineer the software in the machines. I've asked around and both implementations (in OS or in game program) are used.

As you said, it doesn't really matter whether there is a separate instance of the RNG function for each game or paytable and denomination or the same one is used for all. Any change in your luck when you switch game or denomination is just that -- a change in your luck.

As for your second question, there once was a machine that went through a fixed sequence of results. That machine was produced about 100 years ago. Every fourteenth play on the machine was a winner. It didn't take players long to discover the pattern.

Some of the early computer-controlled slots are close to your description. The software running the machine would poll the RNG and determine the result of the next spin at the conclusion of the current spin. The machine would then sit with that result locked in, waiting to be played and to display the result.

As James Maida, president of Gaming Labs International says, "Anytime a machine is sitting with a result locked in it is vulnerable to being cheated." And that's exactly what happened. The Weeks Box is a device that could predict the payout on the next spin on these machines.

As a result, regulators require that RNGs run continuously and that the software not (poll the RNG and) lock in the result until after the player has started the spin or hand. Video poker machines choose the five deal cards when you press the Deal button and they don't choose the draw cards until you draw. The RNG cheat's job is much harder (impossible?) now because the machine is never sitting with a result locked in.

On any machine in a casino today, the result you get is the result determined by values from the RNG at the moment that you started the play or drew to replace discards.

Finally, you made a statement that is incorrect. You said that the "RNG is slowly getting the odds in my favor to hit."

An RNG just generates a stream of numbers. The RNG has no idea whether the numbers are favorable to the players. It is not influenced by any outside forces. An RNG can't get the odds in your favor, slowly or otherwise.

John Robison

John Robison is an expert on slot machines and how to play them. John is a slot and video poker columnist and has written for many of gaming’s leading publications. He holds a master's degree in computer science from the prestigious Stevens Institute of Technology.

You may hear John give his slot and video poker tips live on The Good Times Show, hosted by Rudi Schiffer and Mike Schiffer, which is broadcast from Memphis on KXIQ 1180AM Friday afternoon from from 2PM to 5PM Central Time. John is on the show from 4:30 to 5. You can listen to archives of the show on the web anytime.

#### Books by John Robison:

The Slot Expert's Guide to Playing Slots
John Robison
John Robison is an expert on slot machines and how to play them. John is a slot and video poker columnist and has written for many of gaming’s leading publications. He holds a master's degree in computer science from the prestigious Stevens Institute of Technology.

You may hear John give his slot and video poker tips live on The Good Times Show, hosted by Rudi Schiffer and Mike Schiffer, which is broadcast from Memphis on KXIQ 1180AM Friday afternoon from from 2PM to 5PM Central Time. John is on the show from 4:30 to 5. You can listen to archives of the show on the web anytime.

#### Books by John Robison:

The Slot Expert's Guide to Playing Slots