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#1 2005-07-06 18:48:42

ganesh
Moderator
Registered: 2005-06-28
Posts: 21,102

Creeper

A creeper plant is climbing up and around a cylindrical tree trunk in a helical manner. The tree trunk has a height of 480 inches and a circumference of 32 inches. If the creeper covers a vertical distance of 60 inches in one complete twist around the tree trunk, what is the total length of the creeper? roll


It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#2 2005-07-06 22:34:16

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,619

Re: Creeper

Height = 480 inches.
Creeper gets 60 inches higher each twist, so would need 8 twists to reach the top.
But what length does it grow for one twist?


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

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#3 2005-07-07 03:31:15

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

Re: Creeper

[Removes answer]

Last edited by mathsyperson (2005-07-07 08:14:53)


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

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#4 2005-07-07 11:26:09

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,619

Re: Creeper

Ganesh's Sun is AWESOME


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

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#5 2005-07-07 16:49:57

ganesh
Moderator
Registered: 2005-06-28
Posts: 21,102

Re: Creeper

First, we'd have to convert  the trunk into two dimensions.....
Now, we get a right angled triangle for one twist,
and one side of the triangle is 32 inches, height is 60 inches,
the hypotenuse is square root of
32^2 + 60^2
that is square root of
1024+3600,
eight times this value is the lenght of the creeper;
AND
Thank you, Mr.Administrator, for liking my avatar .


It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#6 2005-07-08 02:11:19

sreenithayyil
Member
Registered: 2005-07-08
Posts: 1

Re: Creeper

Ganesh U r fantastic. u r jokes and problems are good. keep going. thanks
srinithayyil

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#7 2005-07-08 03:17:37

Roraborealis
Member
Registered: 2005-03-17
Posts: 1,594

Re: Creeper

His website is good! What was it again? I forgot...........


School is practice for the future. Practice makes perfect. But - nobody's perfect, so why practice?

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#8 2005-07-08 04:43:39

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

Re: Creeper

That's what I got, before I left it for others to solve. I wasn't sure if you were allowed to flatten it.
Here's his site: http://www.geocities.com/ganesh91569


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

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#9 2005-07-08 09:42:34

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,619

Re: Creeper

I had forgotten that spiral-triangle trick! I was trying to think in 3D and got well confoosed.


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

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#10 2005-07-08 23:53:14

ganesh
Moderator
Registered: 2005-06-28
Posts: 21,102

Re: Creeper

sreenithayyil wrote:

Ganesh U r fantastic. u r jokes and problems are good. keep going. thanks
srinithayyil

Thanks a lot for the compliment, Sreenithayyil !


It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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