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## #51 2013-04-01 09:32:19

anonimnystefy
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### Re: rat run probability

Okay, I will wait till then.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #52 2013-04-01 11:48:35

bobbym

Online

### Re: rat run probability

Hi Agnishom;

I am getting ≈ 0.077 for c).

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #53 2013-04-01 14:11:22

Agnishom
Real Member

Online

### Re: rat run probability

How?

My Approach was like this: P(starting from 1) = (No. of times it starts from 1 and leaves through 3)/(No.of times it leaves through 3)

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'The whole person changes, why can't a habit?' -Alokananda

## #54 2013-04-01 14:16:18

bobbym

Online

### Re: rat run probability

Hi;

That is very difficult to answer when someone gets an programming answer that may be incorrect or may not be.

Your reasoning looks okay. But 35%? Doesn't that seem a little high to you after all it only starts in 1, 25% of the time.

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #55 2013-04-01 14:24:01

Agnishom
Real Member

Online

### Re: rat run probability

You are correct but what should I do now?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'The whole person changes, why can't a habit?' -Alokananda

## #56 2013-04-01 14:27:16

bobbym

Online

### Re: rat run probability

anonimnystefy and I just were discussing c) and he showed me where I was going wrong with it too. This is a difficult one to do by simulation because it has a conditional probability in it.

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #57 2013-04-01 14:38:31

anonimnystefy
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### Re: rat run probability

Are you sure you are counting the events correctly?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #58 2013-04-01 14:40:52

Agnishom
Real Member

Online

### Re: rat run probability

Have you done it?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'The whole person changes, why can't a habit?' -Alokananda

## #59 2013-04-01 14:41:35

bobbym

Online

### Re: rat run probability

Hmmm, you are never sure of anything, I could be making a mistake. That is why I stress having at least two methods. One checks the other.

But do you agree 35% is too high?

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #60 2013-04-01 14:43:25

anonimnystefy
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### Re: rat run probability

#### bobbym wrote:

Hmmm, you are never sure of anything, I could be making a mistake. That is why I stress having at least two methods. One checks the other.

But do you agree 35% is too high?

I was talking to Agnishom.

Hi Agnishom

bobbym has done it and I believe his answer is correct.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #61 2013-04-01 14:57:22

bobbym

Online

### Re: rat run probability

The simulation looks okay to get the numerator and the denominator. I am looking for an analytical solution to back up the simulation!

A very rough analysis gives 1 / 16 which is close to the simulation.

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #62 2013-04-01 15:14:01

anonimnystefy
Real Member

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### Re: rat run probability

Could you run the simulation a gew more times and post the results?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #63 2013-04-01 15:17:20

bobbym

Online

### Re: rat run probability

Same thing, I suspect the exact answer is 1 / 13.

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #64 2013-04-01 15:18:55

anonimnystefy
Real Member

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### Re: rat run probability

1/13 is the correct answer. Remember our friend Bayes?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #65 2013-04-01 15:24:30

bobbym

Online

### Re: rat run probability

He is no friend of mine. Lucky he is long since gone.

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #66 2013-04-01 15:26:44

anonimnystefy
Real Member

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### Re: rat run probability

A figure of speech.

Have you tried using the Bayes' theorem. It gives 1/13, whoch agrees with your simulation!

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #67 2013-04-01 15:28:47

bobbym

Online

### Re: rat run probability

I have not tried it, how did you set it up?

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #68 2013-04-01 15:34:54

anonimnystefy
Real Member

Offline

### Re: rat run probability

Just plugged the numbers in.

P(A|B)=P(B|A)*P(A)/P(B)= (2/13)*(1/4)/(1/2)=1/13.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #69 2013-04-01 15:37:38

Agnishom
Real Member

Online

### Re: rat run probability

A smiley?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
'The whole person changes, why can't a habit?' -Alokananda

## #70 2013-04-01 15:38:21

anonimnystefy
Real Member

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### Re: rat run probability

Ah, thanks, bobbym.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #71 2013-04-01 15:40:17

bobbym

Online

### Re: rat run probability

That looks simplest.

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #72 2013-04-01 21:56:36

anonimnystefy
Real Member

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### Re: rat run probability

It is. I was amazed when I figured it out.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #73 2013-04-01 21:59:21

bobbym

Online

### Re: rat run probability

Yes, you did well. Very good!

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.

## #74 2013-04-01 22:18:44

anonimnystefy
Real Member

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### Re: rat run probability

Thanks. Have you figured out what went wrong in Agnishom's simulation?

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

## #75 2013-04-01 22:20:20

bobbym

Online

### Re: rat run probability

I have not seen it yet. He might have a logic error in the program.

In mathematics, you don't understand things. You just get used to them.
Some cause happiness wherever they go; others, whenever they go.
If you can not overcome with talent...overcome with effort.