Jump to content

Wikipedia:Reference desk/Archives/Mathematics/2009 February 16

From Wikipedia, the free encyclopedia
Mathematics desk
< February 15 << Jan | February | Mar >> February 17 >
Welcome to the Wikipedia Mathematics Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


February 16

[edit]

CASINOS

[edit]

hello:D

i have a high school assignment on probability.. basically, i and my group have to design a simple, creative and original casino game. and we have to explain the winning/losing probabilities of the game and the concept of the game.. how do u suggest we go about creating the game? any possible suggestions? and what are key things we have to consider when creating a new game?

thanks. please respond asap. thanks:D --218.186.12.201 (talk) 09:20, 16 February 2009 (UTC)Pearl[reply]

I suggest something involving dice - they are a very easy way of getting randomness. (You could use coins, but they have fewer options which will probably make the game more boring.) The key thing to remember when making a casino game is that there needs to be a "house edge" - the odds have to favour the casino, otherwise you won't make any money. A very simple game would be for the player to bet some money, then the player and someone from the casino each roll a die, if the player gets a higher roll the casino gives him money equal to his bet, if he gets a lower or equal roll, he losses the bet. The fact that the casino wins when there is a tie is what gives the house edge. I suggest you come up with something a little more interesting, though! --Tango (talk) 11:45, 16 February 2009 (UTC)[reply]
Roulette where the wheel is a Realeaux polygon and the ball is a Meissner tetrahedron. You can bet that's original.Cuddlyable3 (talk) 14:53, 16 February 2009 (UTC)[reply]
Simply giving the house an advantage is one thing, but the most successful games will give the house an advantage without appearing to do so. Or, better yet, they will appear to give the players the advantage. This is why so many carnival games are "fixed". So, let's use this quote about coin tossing from an early post on this Desk: ("It is six times as likely that HTT will be the first of HTT, TTH, and TTT to occur than either of the others" ). So, we could give the players a 2X payout if they manage to flip the TTH or TTT sequence before the HTT sequence, and keep their money otherwise, and they will be certain the odds are in their favor, when they really aren't.
You could also give the players the option to try for HHT or HHH before the THH sequence, with the same 2X payout when they win. This will help if they think the game is fixed in some way. Note that this game requires that they flip the coin continuously and count every sequence of 3. So, don't just count the 1st-3rd sequences and 4th-6th sequences as possible matches, but also look at the 2nd-4th and 3rd-5th coin tosses.
Also note that this doesn't need to use a coin, but any binary event will work. You could use a roulette wheel with black being one outcome and red the other (you'd also need to assign the green zero and double zero to act as either red or black). You could use card draws being red or black, as well. You could use dice throws with odds or evens. StuRat (talk) 18:00, 16 February 2009 (UTC)[reply]
I believe casinos are required by law to publish the odds for their games (in many jurisdictions, probably not all), so that kind of trick doesn't really work. Carnivals are far less regulated. --Tango (talk) 18:12, 16 February 2009 (UTC)[reply]
Yes, but gamblers either don't understand odds or don't care about them, or they wouldn't play at all, would they ? Gamblers tend to go on "instinct", which is frequently wrong, allowing them to be fleeced of their money. StuRat (talk) 18:22, 16 February 2009 (UTC)[reply]
Well, yes, many gamblers are just idiots. Some do know they are likely to lose but consider the enjoyment of playing to be worth it. --Tango (talk) 18:36, 16 February 2009 (UTC)[reply]
Someone said earlier to use dice, which is a good idea. You can design some really cool games with big jackpots and things like that. Like a 6 could pay you $5 AND give you an extra free roll (you could make a lot if you go on a run of 6's). You can do almost anything you want as far as payouts, the only trick is that once you design the game you have to properly calculate the expected payouts and then make the fee to play slightly higher (maybe round up to the nearest dollar for your profit). That is the core of the assignment is being able to calculate what the fair price of the game is and then charge a little more. Having fixed payouts like this in my opinion is easier, but it is more like a carnival game (where you charge $x dollars a try) than a casino game, because most casino games allow you to bet whatever amount you like. Anythingapplied (talk) 22:01, 16 February 2009 (UTC)[reply]
To make the game interesting the player needs to have choices to make along the way. Perhaps the extra roll could cost something (less than the usual bet), so you have to decide whether to take it or not. (That's a pretty rubbish choice - if you're playing the game, then obviously you think the usual bet is a fair price so, of course, you'll take it if it is cheaper, but you get the idea.) --Tango (talk) 22:14, 16 February 2009 (UTC)[reply]
Ideally you want a format where one event influences the likelihood of a second. Card games have this, and the varying nature of the game and the mental activity required to make decisions makes them more involving than games like roulette or craps where you're just betting on chance. At least a semblance of control can make a game much more addictive, as players think skill can recover the losses that luck is responsible for, rather than crediting everything to fortune. 86.8.176.85 (talk) 18:38, 17 February 2009 (UTC)[reply]
If you can pull it off, then great, but it's very hard to make a game like that and ensure that the house will always win (in the long run). For example, Blackjack works like that but casinos have to use multiple decks to reduce the effectiveness of card counting (by making it closer to completely random) because allowing people playing cleverly to make a difference can easily result in the house losing money. --Tango (talk) 18:56, 17 February 2009 (UTC)[reply]

oh my goshh:DD thanks soo much. i found some of the information a lil' hard to understand but im sure a lil reading up will totally help me... thank you so much for ur time and useful help. i knw i can depend on wiki helpdesk anytime..lol :DPearl--218.186.12.201 (talk) 11:36, 18 February 2009 (UTC)[reply]

Didn't understand

[edit]

I couldn't understant the mechanical dialect in this mechanics question.

A drop-forge hammer, of mass 1500kg, falls under gravity on to a piece of hot metal which rests in a fixed die. From the instant the hammer strikes the piece of metal until it comes to rest, the hammer decelerates at 1.5 m/s2.

Find the magnitude of the force exerted by the hammer on the piece of metal (a) while the hammer is decelerating (b) after the hammer has come to rest

Answers written in the book : (a) 17250 N !!!!!!!!!!!!!!WOWOWOWOWOW!!!!!!!!!! (b) 15000 N

PLEASE NOTE THE BOLD PART OF THIS QUESTION, IT MADE ME THINK HARD AND I AM AT ODDS

My View: I understand that there would be a normal reaction force when the hammer hits the metal. Naturally this reaction force would be much greater than the hammer's weight to provide upward acceleration against motion (hammer travels down to hit metal piece) as the flexibility of hot metal allows it.

My question is, why would the downward contact force on piece of metal be 17250 N (force exerted by hammer on metal).

It should be, the force exerted by metal on hammer is 17250N (2250N > weight of hammer) thus exactly what is needed to provide that deceleration ( or upward acceleration against motion). If contact force on metal by hammer is 17250N, reaction would have to be more ( but I don't see how and why this is so).


                 |     |
                 |  ?  |  HAMMER
                 |   ^ |
            |---------------|
            |               |
            |     METAL     |



WHAT ARE YOUR VIEWS PEOPLE? —Preceding unsigned comment added by 202.72.235.202 (talk) 19:04, 16 February 2009 (UTC)[reply]

The key to this kind of question is not to worry about the scenario but just to extract the relevant information. The relevant information here is that the hammer has a mass of 1500kg and is decelerating at 1.5 m/s2. Those are the only two facts you need to know. --Tango (talk) 19:15, 16 February 2009 (UTC)[reply]
Item b is the weight of the hammer only. Item a is the weight (W=mg) plus the force required to decelerate that mass at that rate (F=ma). It's also apparent from the answers that they use the rather imprecise value of g=10m/s2, rather than 9.81. Also, while not part of the problem, you should realize that not all of the force exerted on the metal is passed on to the die. Some of the force is converted into heat and noise or used to deform the metal. StuRat (talk) 03:05, 17 February 2009 (UTC)[reply]

Also, while not part of the problem, you should realize that not all of the force exerted on the metal is passed on to the die. Some of the force is converted into heat and noise or used to deform the metal. NO. --76.167.241.45 (talk) 06:42, 18 February 2009 (UTC)[reply]
Are you going to explain ? Do you not believe that metal is heated by the stamping process ? Do you not believe that sound results ? Where do you think the energy comes from to create this heat and noise ? StuRat (talk) 16:32, 19 February 2009 (UTC)[reply]
First of all, "force" and "heat and noise" are not even the same kind of thing. The latter is energy; force does not "convert" into heat. That's like saying my sister converted into two hours. Second, force is the time derivative of momentum, and momentum is conserved; so as long as the same momentum is transmitted over the same period of time, the average force is completely determined. So the notion that somehow "force" can be "lost" lacks any merit. --71.106.173.110 (talk) 05:02, 20 February 2009 (UTC)[reply]
It sounds like you think that forces and energy are completely unrelated. They are, in fact, closely related. From our energy article it says that energy "describes the amount of work that can be performed by a force". When talking about a time derivative, a better analogy would be velocity and acceleration. In this case, changing the rate of acceleration will affect the final velocity. And, again, where do you say that the energy to produce the heat and noise magically comes from ? StuRat (talk) 05:34, 20 February 2009 (UTC)[reply]
I'm saying that "not all of the force exerted on the metal is passed on to the die" is completely false. "Force" that is exerted by one object on a second object either accelerates the second object, or the second object has to exert the same force on a third object, etc. 100%. If the hammer exerts a force on the metal, then if the metal doesn't accelerate in the end, it must transmit all of the force to the die. The only connection between force and energy is that when a force moves something over a distance, then work is done; but force can be exerted without moving anything (e.g. between the metal and the die), and therefore without any energy being involved.
If you want to change the topic to talk about energy, then in fact none of the energy of the hammer is passed on to the die (no kinetic energy anyway, as it doesn't move). I will answer your question: the heat and noise come from the kinetic energy of the hammer; I don't think it's magic; and I don't think it somehow takes away from the transmission of any "force" either. --71.106.173.110 (talk) 08:31, 20 February 2009 (UTC)[reply]
Moving something over a distance is one type of work, but there are others, like heating a material (work (thermodynamics)). Note that you can get heating from a force without any kinetic energy. Placing a weight on a contained gas will cause it to compress and heat up. Where is this heat coming from ? StuRat (talk) 15:24, 20 February 2009 (UTC)[reply]