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**hootyhoo****Member**- Registered: 2017-03-11
- Posts: 4

Hi, all. I am not sure I put this put in the right category, but I'll ask anyways.

The problem I am stuck on tells me to consider a small machine with only two cups. And for that small machine I have to find out the probability of a ball landing in each cup. Then, I have to repeat this process for other machines with 3, 4, and 5 cups. From there I have to use any pattern I see and derive an expression for the probability of landing in the i^th cup from the left in a machine with n cups.

We also have to right the probabilities as fractions (not simplified) so we can find patterns.

Does anyone mind helping me with this?

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,496

Hi;

I would love to help but to help I need to see a bit of what you have already done and a bit of what you already know.

Some questions, how many balls are put into the cups? Are the cups equiprobable?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**hootyhoo****Member**- Registered: 2017-03-11
- Posts: 4

Oh yes, sorry for not including the number of balls. It's 40.

And this is what I have so far:

And for task one (the task before this one), I had to do an experiment using a pinball machine with 5 cups. (40 balls too):

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,496

Hi;

I have fixed your post to show the images. You do notice that this is close to a standard normal curve.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**hootyhoo****Member**- Registered: 2017-03-11
- Posts: 4

Now that you mention it, yes. And thank you for the fix.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,496

I think you are attempting to build theoretically a quincunx.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**hootyhoo****Member**- Registered: 2017-03-11
- Posts: 4

Okay, I can see that now. I have neber heard of a quincunx so I looked more into it using this page: link removed by moderator

It says the forumla to solving the probability of a machine like this is binomial distribution. I will try making an expression witht aht and then I will let you know how it goes.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 108,496

That page just leads me to a link with a bunch of gals in various stages of eating disorders...

Post when you are done and good luck.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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