Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

Hi;

A huge regular polygon has been constructed in the desert with 100 sides. Each side is 1 mile long. A pursuit robot of the type talked about here http://www.mathisfunforum.com/viewtopic.php?id=20067 but greatly enhanced is made to run perfectly along the perimeter. When it begins each side the robot increments its speed by1 mph. So at side 1 it will travel at 1 mph, at side two 2 mph, at side three 3 mph etc. At the last side the robot will be traveling at a dazzling 100 mph.

191 technicians are in a bunker close by to observe the pursuit robots performance. They must remain inside the bunker because if they are sighted by the robot it will pursue them. The test begins and the robot performs perfectly. 1 mph for the first side, 2 mph for the second side, 56 mph for the 56th side and 100 mph for the last side.

When the test is completed, the chief engineer/instructor comes into the room. He begins to ask the technicians questions about the robot's performance. The technicians want to impress the questioner so they raise their hands eagerly with their answers. The questions continue, some tough, some very easy.

The questioner asks what was the average speed of the robot. 190 hands shoot up with answer and one guy in the back says, "hold it, I need a bit more time." The rest turn around to stare at him for his stupidity. The questioner immediately to their dismay dismisses the 190 and begins questioning the "stupid guy." We do not know what he says to him because we have been dismissed.

The question is what happened here?

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,889

Hi bobbym

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

Hi anonimnystefy;

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

The last guy did not have a CAS, that is what happened.

'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'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

Offline

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,559

Hmm... the technicians would not likely fall into the "50 mph" trap, so we may assume their answer is technically correct.

So "stupid guy" must be including some other fact.

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

Offline

Maybe he was working on a generalissd formula for a polygon with n-sides

'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'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

Offline

**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi Bobby,

*Last edited by phrontister (2014-06-07 14:00:52)*

"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

Offline

Its v=d/t by the way

'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'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

Offline

**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Oops...thanks! >blush<

I've corrected my post.

"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

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

Lots of interesting answers.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

Shall we consider the robot to be a point sized object?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

I would consider it horse sized. Check out the vids and watch it do the horsey dance.

**In mathematics, you don't understand things. You just get used to them.**

Offline

Funny but a non-point size object has a problem. Consider the vertices at which the robots make a turn: a point on the robot nearer to the interior of the polygon moves a lesser distance as compared to a point situated further from it.

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

Offline

**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi Agnishom,

That reminds me of this.

"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

Offline

That is nice but do you have any idea on what 'brittle math' reffers to?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

Offline

**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

No, I've never heard that term before. Googling it didn't turn up anything that helped enlighten me, either.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

It is brittle and like all things that are brittle...

Funny but a non-point size object has a problem. Consider the vertices at which the robots make a turn: a point on the robot nearer to the interior of the polygon moves a lesser distance as compared to a point situated further from it.

You are actually attempting to apply reality to that story?

**In mathematics, you don't understand things. You just get used to them.**

Offline

**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Yes, when I first saw the thread's title I knew there would be some significance in the meaning of 'brittle' ("apt to break, easily broken; frail; curt, edgy, sensitive; unstable") as relating to the puzzle, but then, as now, I haven't been able to make the connection.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

Have you read brittle math 1? They are connected, part of an aptitude test. There will be more.

**In mathematics, you don't understand things. You just get used to them.**

Offline

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,559

Length of robot?

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

Hi;

Length of robot?

I am not following you.

**In mathematics, you don't understand things. You just get used to them.**

Offline

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,559

Just trying to think of everything. I meant that perhaps the length of the robot needs to be factored in, but it would be negligible compared to the course, and we could assume the front of the robot as the reference point for calculations anyway.

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

bRittle math 1 is not asking any question. How can I answer that?

Has brittle math 2 got anything to do with relativity?

*Last edited by Agnishom (2014-06-08 19:17:16)*

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,879

**In mathematics, you don't understand things. You just get used to them.**

Offline