A shuffle through the Gaming mailbag:

Q. Tell me about Hundred Play Poker. The one machine at the casino near me has 8-5 Double Double Bonus, the same as on the quarter single-hand games, but not as good as the 9-6 DDB on one-hand dollar games. You can play Hundred Play for pennies, two cents or nickels.

Is there any advantage to playing all the hands at Hundred Play, or is it OK to play fewer? Will I get a higher payback if I play nickels instead of pennies? I play quarter Triple Play and Five Play sometimes, but I’m not sure what to be careful of in Hundred Play.

A. The average payback percentage with expert play in 8-5 Double Double Bonus Poker is 96.79 percent regardless of whether you’re playing one hand, 10 hands, 100 hands or anything in between.

Likewise, the payback percentage does not change with coin denomination. It’s the pay table that determines the percentage, not the denomination of your bet.

It’s perfectly fine to play fewer than 100 hands at Hundred Play. That will not affect your payback percentage.

Hundred Play tends to smooth out volatility compared to playing fewer hands. Given the same overall bet size, you’re unlikely to lose as fast in the bad times on Hundred Play than on a single-hand game, but also unlikely to win as big in the good sessions.

Let’s make the maximum bet of \$5 on Hundred Play pennies, and the same maximum bet on a dollar single-hand game. There will be many hands on which you lose the entire \$5 on the single-hand game, but on Hundred Play the loss almost always is cut down by a few winners.

On the other hand, on a royal flush on the dollar game, you’ll collect \$4,000, while on penny Hundred Play, each royal is worth only \$40. You need all 100 to get to \$4,000, and that’s very rare.

I would note that if you’re playing all 100 hands for pennies and betting \$5, the better bet in your casino is to play the dollar game with the 9-6 pay table. Average payback with expert play on 9-6 DDB is 98.98 percent. If you’re playing fewer than 100 hands and need to bet less, then choose the game that allows you to stay within your bankroll.

Q. I saw something strange at the blackjack table. This guy wanted to double down on blackjack. They wouldn’t let him. He got a little belligerent and demanded to know why he couldn’t play the hand his way, and was told, “House rules.” He wanted to carry on with his rant, and eventually a suit told him, “Those are the rules on file with the gaming control board. We have to pay blackjacks.”

It got me wondering what the odds really are if you want to double on blackjack, just as if the Ace was a 1 and you were double on any other 11.

A. If blackjacks pay 3-2, then you’re getting \$1.50 for every \$1 of your wager. Should you find yourself playing 6-5 blackjack — heaven forbid — winnings decrease to \$1.20 of your wager.

When you double down, your average winnings decrease to 67 cents per dollar of your original wager. Note the “original wager” part. You’re not getting 67 cents on your first bet and another 67 for your double bet. Just 67 cents.

You’re going to lose sometimes when you treat your blackjack as an 11 and double down. You’re going to push on common dealer 21s, not just on blackjacks. Paying all blackjacks and refusing doubles is a good rule for players.