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## #1701 2013-04-14 11:59:10

Agnishom
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### Re: Is this cool with you?

That is where I am getting those problems from

'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

## #1702 2013-04-14 13:47:27

anonimnystefy
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### Re: Is this cool with you?

I wonder if bobbym has a devious variation of the last problem he will be posting soon.

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

## #1703 2013-04-14 14:58:49

bobbym

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### Re: Is this cool with you?

Nothing devious ever entered my mind.

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.

## #1704 2013-04-14 15:01:58

anonimnystefy
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### Re: Is this cool with you?

I would call many of the problems you pose devious. The 9's problem is pretty devious if you ask me...

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

## #1705 2013-04-14 15:06:11

bobbym

Online

### Re: Is this cool with you?

It is not devious, just impossible,

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.

## #1706 2013-04-14 15:08:42

anonimnystefy
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### Re: Is this cool with you?

Impossible => devious.

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

## #1707 2013-04-14 15:10:39

bobbym

Online

### Re: Is this cool with you?

It is computationally pretty simple if I just had someplace to put the numbers...

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.

## #1708 2013-04-14 15:14:53

anonimnystefy
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### Re: Is this cool with you?

Anyway, can we expect a new problem here soon?

Oh, and, speaking of problems, how's your back doing?

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

## #1709 2013-04-14 15:16:16

bobbym

Online

### Re: Is this cool with you?

Worse than ever.

A supercomputer? No one in their right mind would let me near one.

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.

## #1710 2013-04-14 15:19:14

anonimnystefy
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### Re: Is this cool with you?

I am sorry to hear that. Have you been to a doctor?

Well, I'm guessing you would either rule the world or break the supercomputer.

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

## #1711 2013-04-14 15:23:39

bobbym

Online

### Re: Is this cool with you?

Doctors? Thanks to them I have extra problems.

I would try to take it apart and break 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.

## #1712 2013-04-14 15:27:05

anonimnystefy
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### Re: Is this cool with you?

The only problems doctors can cause you are money problems. I suggest you visit him. Or at least go and get a massage.

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

## #1713 2013-04-14 17:34:30

bobbym

Online

### Re: Is this cool with you?

I wish that were true. I prefer the pain rather than the lizard.

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.

## #1714 2013-04-14 21:05:05

anonimnystefy
Real Member

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### Re: Is this cool with you?

They've always helped me so far.

When can we expect a new problem in here?

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

## #1715 2013-04-14 21:19:03

bobbym

Online

### Re: Is this cool with you?

I am being kept busy fighting spammers, monitoring arguments and answering homework questions.

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.

## #1716 2013-04-14 21:24:37

anonimnystefy
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### Re: Is this cool with you?

Which homework questions?

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

## #1717 2013-04-14 21:35:24

bobbym

Online

### Re: Is this cool with you?

http://www.mathisfunforum.com/viewtopic.php?id=19217

I still do not have any idea what he even wants. I ask a question he avoids it and goes on explaining something else. This is very non productive.

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.

## #1718 2013-04-14 21:38:48

anonimnystefy
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### Re: Is this cool with you?

Oh, that. It does seem pretty unclear what he wants.

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

## #1719 2013-04-14 21:45:30

bobbym

Online

### Re: Is this cool with you?

He will not explain or point me to the book, title and author. I am sure it is stated better there.

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.

## #1720 2013-04-17 12:16:50

anonimnystefy
Real Member

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### Re: Is this cool with you?

#### bobbym wrote:

New Problem:

A used car salesman has 8 lots with 100 cars each. He wants to repaint all his cars. Each day one of his employees picks 35 cars at random from all his cars and paints them. Then he returns them to the lots. Since they do not keep records some cars get painted more than once. After 23 days the manager would like to know how many cars have been painted. he wants to do this without going down to the lots. Can you figure it for him?

A says) 522.
B says) I do not have an answer but I know that A's answer is wrong.
C says) I got that, and it is definitely wrong.
E says) I got it!

This can also be done using linearity of expectation.

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

## #1721 2013-04-17 14:31:45

bobbym

Online

### Re: Is this cool with you?

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.

## #1722 2013-04-17 18:33:32

anonimnystefy
Real Member

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### Re: Is this cool with you?

Well, I just give each car a random variable which is 1 if the car is painted and 0 if not. Its expected value is E[Xi]=1-(1-35/800)^23. The expected number of painted cars is E[X1+X2+...+X800], which, based od linearity of expected value, equals E[X1]+E[X2]+...+E[X800]=800*(1-(1-35/800)^23), which gives the correct answer.

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

## #1723 2013-04-17 19:36:37

bobbym

Online

### Re: Is this cool with you?

Hi;

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.

## #1724 2013-04-18 00:29:06

anonimnystefy
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### Re: Is this cool with you?

I like that it can be easily generalized.

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

## #1725 2013-04-18 00:34:58

bobbym

Online

### Re: Is this cool with you?

Did you see my solution?

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.