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#351 2010-08-31 17:39:55

jimmyR
Member
Registered: 2009-05-29
Posts: 143

Re: What do you think?

Hi bobby;

You know who, has solved another of yours. I have worked it out and her answer is correct. She texted to me for you.

Prob 3:

How many permutations of 3 letters can you make out of the word:

clandestine?

Hi Bobby;

Isn't this supposed to be problem 4? The answer is 552. I have one how many 5 letter permutations can you make out of erroneously?

Bye!

Elaina

I saw her work it is mostly casework.

Last edited by jimmyR (2010-08-31 17:41:36)

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#352 2010-08-31 17:45:05

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

Re: What do you think?

Hi jimmyR;

Where are you? Your address is really close by, the Sahara?

Hi Elaina;

552 is correct as regards to your problem I will submit an answer as soon as I can.


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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#353 2010-08-31 17:48:09

jimmyR
Member
Registered: 2009-05-29
Posts: 143

Re: What do you think?

I am in the office. You know the complex. She is on the waiting list  here. She thinks that she has given you a tough problem. She doesn't know about you and generating functions and he hasn't taught her that yet.

Last edited by jimmyR (2010-08-31 17:52:33)

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#354 2010-08-31 17:51:52

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

Re: What do you think?

Hi jimmyR;

Yes, if I were going to use casework as she has done that would be tough. I know
she is on the waiting list. Thank the lord there are no apartments available right now.


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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#355 2010-08-31 17:53:32

jimmyR
Member
Registered: 2009-05-29
Posts: 143

Re: What do you think?

When she reads that... You know she does everything opposite to what you ever told her.

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#356 2010-08-31 17:54:51

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

Re: What do you think?

Hi jimmyR;

I know that. She always was a pain.


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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#357 2010-08-31 17:57:12

jimmyR
Member
Registered: 2009-05-29
Posts: 143

Re: What do you think?

That guy is posting about a Cauchy product for 2 series. Do you see it? How come you are not taking that man?

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#358 2010-08-31 17:59:03

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

Re: What do you think?

Hi jimmyR;

I don't really want work on that right now. I am kind of tired of series.


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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#359 2010-08-31 18:41:28

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

Re: What do you think?

Elaina VW wrote:

I have one how many 5 letter permutations can you make out of erroneously?

Because you worked these problems with essentially the wrong method, the work was
hard. Here is my way:

And for my problem:

bobbym wrote:

How many 3 letter permutations can you make out of clandestine?


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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#360 2010-09-03 07:38:02

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

Re: What do you think?

A real killer!

A man walks through a tunnel. Two thirds of the way through he sees a car heading for him. The car is moving at 75 mph. If he starts to run he can get to either end of the tunnel just as the car does. What is the speed in mph of the running man?

A says) Impossible! You have to know the distance the car is from the man.
B says) I don't think so, but I am unable to solve it.
C says) I solved it. It was easy. The man is moving at 25 mph.
D says) I agree with B. It can be solved but C's answer is wrong. But I can't prove it.

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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#361 2010-09-04 09:07:21

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

Re: What do you think?

Hi jimmyR, Fruityloop and Elaina VW.

This is an addenda to post # 348.

bobbym wrote:

Same answer as the integral provided in post #335. Is this an improvement? I don't think so but it is I believe a new method.

I am sorry to say all of that has been covered in the book."Experimentations in Mathematics" p 36 -. There you will even see my formula (1.52). Apparently we both derived it from the same integral while doing a CCP. I went on to use the formula while he goes on proving concavity.

That at least proves my method is okay. Also it is somewhat gratifying to have come up with the same idea as a Borwein or a Bailey. Difference is, they arrived at it through skill, I got there by 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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#362 2010-09-06 11:25:03

Fruityloop
Member
Registered: 2009-05-18
Posts: 143

Re: What do you think?

A real killer!

A man walks through a tunnel. Two thirds of the way through he sees a car heading for him. The car is moving at 75 mph. If he starts to run he can get to either end of the tunnel just as the car does. What is the speed in mph of the running man?

A says) Impossible! You have to know the distance the car is from the man.
B says) I don't think so, but I am unable to solve it.
C says) I solved it. It was easy. The man is moving at 25 mph.
D says) I agree with B. It can be solved but C's answer is wrong. But I can't prove it.

What do you think?

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#363 2010-09-06 12:01:08

Fruityloop
Member
Registered: 2009-05-18
Posts: 143

Re: What do you think?

This is a little challenging...
Prove

Last edited by Fruityloop (2010-09-06 12:04:34)

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#364 2010-09-06 13:06:37

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

Re: What do you think?

Hi Fruityloop;

It is a good one!

The answer for post #361 ( A real killer ) is correct, 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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#365 2010-09-17 13:58:08

Fruityloop
Member
Registered: 2009-05-18
Posts: 143

Re: What do you think?

Very good Bobbym!
You never cease to amaze me.
Ok.  Try this one...

Last edited by Fruityloop (2010-09-17 14:12:48)

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#366 2010-09-17 22:13:57

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

Re: What do you think?

Hi Fruityloop;

You never cease to amaze me.

Thanks. If only someone who was dating me felt that way.


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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#367 2010-09-29 12:04:45

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

Re: What do you think?

A real killer!

Using all capital letters. Form a word that has 5 acute angles, 2 obtuse angles, and 5 right angles.

I have done the hard work for you. Using the typesetting of the letters in the picture below you get.

Each set has a letter and the number of acute, obtuse and right angles for that letter. For instance:

{A, 3,2,0} means the letter A has 3 acute, 2 obtuse and no right angles.

A says) Besides from the well known PANT there is only 1 other solution for 4 letters.

B says) Nope! There are several four letter word answers for the above set.

C says) B is right and there is also a 3 letter word.

D says) I am no longer good with letters.


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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#368 2010-10-04 16:56:37

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

Re: What do you think?

Super easy!

Prove that:

Without using any particular value of sin(x) or cos(x).


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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#369 2010-10-19 14:20:40

Fruityloop
Member
Registered: 2009-05-18
Posts: 143

Re: What do you think?

Prove that ...

Ok.  I believe I have a proof by contradiction. 

Last edited by Fruityloop (2010-10-19 14:31:40)

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#370 2010-10-19 16:42:02

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

Re: What do you think?

Hi Fruityloop;

That is one way of doing it. Very good!


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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#371 2010-10-21 19:45:55

jimmyR
Member
Registered: 2009-05-29
Posts: 143

Re: What do you think?

Hi bobbym;

I have a post or two from you know who!

Hi bobbym;

How are you? How is the little footsie, better yet? Want to start a forum with us? You would be the administrator and I would moderate.

I have solved the car and tunnel problem #361. I have 25 mph. Can I see what you did?

Elaina

Last edited by jimmyR (2010-10-21 19:46:51)

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#372 2010-10-21 20:42:42

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

Re: What do you think?

Elaina wrote:

How are you?

Fine.

Elaina wrote:

How is the little footsie, better yet?

No!

Want to start a forum with us?

Double No!

Elaina wrote:

You would be the administrator and I would moderate.

That is very magnanimous of you to let me be the boss. So, you would be a moderator. I hate moderators of all types. It is appealing to be able to ban you. Tell me more!

Elaina wrote:

Can I see what you did?

You most certainly can. I will post it shortly I am eating now. I am done.


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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#373 2010-11-21 23:06:05

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

Re: What do you think?

A brand new problem and it is so easyyyyyyy!

A guy counts a deck of cards face down and notices that 5 are missing. He wonders what is the chance that the top card is an ace?

A says) probability is so boring, because I always get it right. I use my genetic algorithms! The answer is simple.

B says) That is not right, the answer is much simpler than that.

C says) I did a simulation and A is right on the money, baby!

D says) I have to go with A. He is much smarter than B and that is good enough for me.

A with head raised, shoulders back and pipe lit says,"Well B, wrong again huh!"

Who is right?


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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#374 2010-12-14 02:50:41

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

Re: What do you think?

Who eats the pie?

A,B,C,D and E decide to stop arguing and to do something together for a change. B's Mom bakes them a big pie to celebrate their togetherness. Before they start to eat they begin to argue about primes. They are mathematically inclined after all. They settle down on this one particular question.

If we start with the set of all fractions with 1 as the numerator and all the primes as denominators ( { 1 / 2, 1 / 3, 1 / 5, 1 / 7, 1 / 11, ...} and each of us starting with A and in order ( A,B,C,D,E, A,B,C,D,E... ) takes the next fraction and eats that amount of the remaining pie. In other words A eats 1 / 2, B eats 1 / 3 of the remaining half, C eats 1 / 5 of the remaining sixth... When we get to E and if there is more pie left we start again with A. The question is will we ever finish the pie?

A says) Since this can go on forever I think there will always be some pie left.

B says) Not necessarily sometimes an infinite process can equal a finite number. I think the pie will eventually be consumed.

C says) Who cares I am hungry.

D says) No wait, I think I read about something like this called Zeno's paradox.

E says) Hey D, did you make that up?


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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#375 2010-12-15 23:45:32

123ronnie321
Member
Registered: 2010-09-28
Posts: 128

Re: What do you think?

hi bobby,

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