Skip to main content
You have permission to edit this article.
The nitty gritty on number generators

The nitty gritty on number generators

  • 0
Craps Table

A shuffle through the Gaming mailbag:

Q. On slot machines with multiple coin denominations, does every game have its own random number generator? What about machines that have multiple games? Are there different generators for each game?

A. Not necessarily. The same RNG can drive results for different games and different payback percentages.

The RNG does nothing but generate random numbers. It doesn't tell the reels where to stop, nor does it tell the game to launch a bonus event. That's up to other portions of the programming.

Numbers from the RNG are mapped onto possible outcomes. If the game designer needs more frequent bonus events in a higher-paying version of a game, it can use number that are mapped onto other symbols in the low-paying game onto bonus symbols in the high payer. If there's a game that doesn't have bonus events, numbers mapped on to bonus combinations in other games can be mapped onto other combinations instead.

In the casino world, RNGs are single-purpose devices, adaptable to any number of games.

Q. I'm not a craps fanatic, but I've played maybe five or six times a year for 10 years or so. I knew all the major bets years ago, or at least I thought I did.

When I was playing at a $10 table a few weeks ago, a player called out "$64 across." The dealer then took his chips and covered all of the point numbers.

Are those just place bets, or is there some secret sauce? If they're just place bets, there are some high house edge bets in there.

A. Yes, $64 across at a $10 table is telling the dealer you want table minimum place bets on all the point numbers. It comes to $10 wagers on 4, 5, 9 and 10 and $12 bets on 6 and 8. You want bets on 6 and 8 to be in multiples of $6 to take advantage of 7-6 odds paid on those bets.

You are correct that the combination includes high house-edge wagers. The edge is only 1.52 percent on 6 or 8, but rises to 4 percent on 5 or 9 and 6.67 percent on 4 or 10.

Sometimes, those who bet the place numbers across are looking for a quick strike. You don't have to play place bets until there is a decision. You can take them down at any time.

With five ways each to roll 6 and 8, four each to roll 5 and 9 and three each to roll 4 and 10, there are 24 winning rolls. There are only six losers -- the six ways to roll 7. If the roll is 2, 3, 11 or 12, it does not affect the place bets. The money just stays in action unless you tell the dealer to take it down.

With 24 winning rolls and six losers, there is an 80 percent chance of winning one bet on the first deciding roll, with wins of $18 on 4 or 10 with 9-5 pays $14 on the other place numbers, with 7-5 pays on 5 or 9 and 7-6 on 6 or 8.

The problem comes if the first deciding roll is a 7. That sinks all bets and you lose the whole $64. The six times you lose $64 per 30 decisions outweighs all the smaller wins combined.

Craps gives players many opportunities to bet combinations that will win more often than they lose. Betting the place numbers across is one of them. But combos don't change the house edge. Losses are costly and the house makes its expected percentage.


Be the first to know

* I understand and agree that registration on or use of this site constitutes agreement to its user agreement and privacy policy.

Related to this story

Most Popular

Get up-to-the-minute news sent straight to your device.