Math Is Fun Forum

MathsIsFun

Administrator

Registered: 2005-01-21

Posts: 7,713

New Puzzles 4

Even more "Stephen Froggatt" puzzles::

Pet Show
Newspaper Caper
Three Of The Best
A Brave Puzzle
A Weighty Problem
The Make-You-Very-Cross Number
NIM-ble Thinking
MatheMusic
A Hole New Board Game
Matches Of The Day
Ancestrally Speaking
Have You Herd Of Cows

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

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: New Puzzles 4

hi

Sorry ... bit of a rush.

Weighty Puzz think I have another soln.

More later

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: New Puzzles 4

Hi MIF;

Funny that Bob and I went for the same problem.

For the weighty problem there are 10 solutions to the problem. Not counting permutations. Want to add the rest? Hope I did not prune out any others.

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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.

MathsIsFun

Administrator

Registered: 2005-01-21

Posts: 7,713

Re: New Puzzles 4

Great! I will put that in the solution.

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

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: New Puzzles 4

Hi MIF;

A mathematical solution would be nice but I do not have one.

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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.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: New Puzzles 4

I would think there is one, thought it does seem GFs might be of use.

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“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.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: New Puzzles 4

Hi anonimnystefy;

GF's usually count the number of solutions not the type of solutions. For that, I usually call on number theory.

Still in all a gf played an important part in the program. Without it there would be no program.

---

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.

Thurhame

Member

Registered: 2013-03-03

Posts: 6

Re: New Puzzles 4

There is a problem with the "Three Of The Best" puzzle.
The puzzle claims there are two solutions to "1+(1/(1+(1/...)))". However, it actually converges to the golden ratio

, meaning there is only one solution.

MORE COMPLEX PROOF:
The formula is the limit as n goes to infinity of the sequence

defined by

.
Assume some

exists (otherwise the sequence would be undefined).
Define a sequence

.
We proceed by induction.
Base step:

Inductive Hypothesis:

Thus we have proved by induction the relation

for all

.
Since

is a sequence of the form

, this ratio converges to the golden ratio.

Last edited by Thurhame (2013-03-05 13:28:02)

Agnishom

Real Member

From: Riemann Sphere

Registered: 2011-01-29

Posts: 24,996

Website

Re: New Puzzles 4

Wonderful, Thanks!

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'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'
I'm not crazy, my mother had me tested.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: New Puzzles 4

Hi Thurhame

Can you specify where it was claimed that 1+1/(1+1/(1+...)) is equal to 2?

---

“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.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: New Puzzles 4

Hi;

The answer given is 2 when it should be the golden ratio.

---

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.

Thurhame

Member

Registered: 2013-03-03

Posts: 6

Re: New Puzzles 4

Hi Thurhame

Can you specify where it was claimed that 1+1/(1+1/(1+...)) is equal to 2?

Oh, my mistake, it just said there were two solutions to the formula. However, that's still wrong; my proof shows that any solution must be equal to the golden ratio, i.e. there are at most 1 solutions.

Edited my post above. Thanks!

Last edited by Thurhame (2013-03-04 05:26:01)

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: New Puzzles 4

Hi Thurhame

Yes, with that I agree. The answer should be one. I think they didn't consider that the number must be positive.

---

“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.

Thurhame

Member

Registered: 2013-03-03

Posts: 6

Re: New Puzzles 4

Ah, thanks for reminding me, my simple less-rigorous proof isn't adequate if i'm only proving the number of solutions, rather than the value. Removing it now. Hope the more complex proof doesn't make anyone's eyes glaze over.