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#226 2010-05-03 19:28:18

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Hi;

I am not seeing it that way. With your assumption that their is no cost 13 is the max but with the assumption that the price they charge is the cost ( or penalty ) then it is not. That is what the question implies according to B: B's reasoning is correct based on that assumption.

P(1) = 75 sold and 3 unsold which has a cost of  -3. Profit 72

P(2) = 72 sold and 6 unsold which has a cost of  -12 Profit 132

P(3) = 69 sold and 9 unsold which has a cost of  - 27 Profit 180

The negative numbers are where the 3x^2 comes from.


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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#227 2010-05-03 19:44:47

ZHero
Real Member
Registered: 2008-06-08
Posts: 1,889

Re: What do you think?

Hey... bobbym!!!

bobbym wrote:

... the price they charge is the cost ( or penalty ) then ...

yeah.. that can be a case!!  up    but it sounds ridiculous! roll

bobbym wrote:

... P(3) = 69 sold ...

lol    shame   roflol


If two or more thoughts intersect, there has to be a point!

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#228 2010-05-03 19:47:08

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Hi;

I am in full agreement there, I think B is ridiculous also.


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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#229 2010-05-03 20:07:31

ZHero
Real Member
Registered: 2008-06-08
Posts: 1,889

Re: What do you think?

yeah.. last night i thought for more than an hour over the problem figuring out the difference between A's and B's statements.
humorously enough, its similar to tha phrontister's "extra $2 and the missing $" problem!


If two or more thoughts intersect, there has to be a point!

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#230 2010-05-04 10:15:14

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Tough:

Prob 48

n people check their scarf and coat in at a large restaurant, each receives a slip. The slips are misplaced and the attendant is forced to randomly choose which scarf and coat to give each person. What is the probability as n approaches infinity that no one gets either a scarf or a coat that is his?

A) says P = 1.
B) says 1 / (2 e )
C) says 1 / e
D) says 1 / e^2
E) says 0

What do you think?


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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#231 2010-05-06 22:12:02

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

A real dilly!

Prob 49

A sequence follows the pattern of.

1,3,1,3,3,1,3,3,3,1,3,3,3,3,1,3,3,3,3,3,1....

First two terms sum to 4. First 8 terms sum to 18. What does the 10001 term sum to?


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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#232 2010-05-08 03:08:15

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Easy one:


Prob 50

If:


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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#233 2010-05-08 03:18:40

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: What do you think?


Why did the vector cross the road?
It wanted to be normal.

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#234 2010-05-08 04:45:23

ZHero
Real Member
Registered: 2008-06-08
Posts: 1,889

Re: What do you think?


If two or more thoughts intersect, there has to be a point!

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#235 2010-05-08 05:49:21

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

That answer is correct I believe! Good work.


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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#236 2010-05-09 07:04:48

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: What do you think?

Hi Bobby,

Last edited by phrontister (2010-05-10 09:27:23)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#237 2010-05-09 07:12:13

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Hi phrontister;

That is correct. Interesting solution, one that I din't know.


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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#238 2010-05-09 12:51:40

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: What do you think?

Hi Bobby,

I found that my 13133... sequence formula gives an incorrect answer for the last element of each segment.

I've corrected it, and I think that it now works for all cases.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#239 2010-05-09 12:59:57

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Hi;

But you got the right answer, it must not have affected the calculation.


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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#240 2010-05-09 13:13:54

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: What do you think?

No, it didn't. For some reason the sum at the end of each segment was 2 less than what it should have been. All the others - the intermediates and the first element of segments - were fine.

Adapting the formula that solves for n was my undoing.

Last edited by phrontister (2010-05-09 13:28:29)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#241 2010-05-09 14:06:57

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Anybody, want to see my solution?


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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#242 2010-05-09 14:18:00

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: What do you think?

Yes, please! I'm very interested to see it. smile


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#243 2010-05-09 14:57:59

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Hi phrontister;

Calm down my friend, remember your arteries. I will post it right here.


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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#244 2010-05-09 22:23:29

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: What do you think?

bobbym wrote:

Calm down my friend, remember your arteries.

Is that a problem for a 27-year-old? My ticker's motoring along well and my blood pressure's normal.

That bus will probably get me, though; or (and this is MIF's fault) sleep-deprivation-induced organ malfunction.

Not that I'm very clever on the keyboard...here's my best effort, which I recorded while trying out some buttons on a synth I had. If you have the stamina and determination to hear it right through to the end you'll hear quite a range of instruments and effects. You may also think that I recorded it on a windy day with the door open...but I didn't.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#245 2010-05-09 22:30:12

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Hi phrontister;

Wunderbar! It made me start dancing.


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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#246 2010-05-09 22:43:40

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: What do you think?

Publish your performance on YouTube. Some greats started that way.

Maybe not with dancing, though...although you could break new ground. That is, if you don't fall over!

Last edited by phrontister (2010-05-09 22:45:46)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#247 2010-05-09 22:46:20

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

I do have an upcoming vid for youtube. It will answer many questions. I will say no more.


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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#248 2010-05-09 22:48:16

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: What do you think?

I'll try to think up some questions before I see the production.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#249 2010-05-09 22:51:49

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Unfortunately or fortunately, these are not questions that you are asking. Or are likely to be asking in the near future.

These are questions being asked by other members about me.


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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#250 2010-05-10 04:35:26

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: What do you think?

Here is my solution to the sequence problem:


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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