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

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 23,051

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?

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.

Offline

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,653

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

Offline

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

[Removes answer]

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

Why did the vector cross the road?

It wanted to be normal.

Offline

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,653

Ganesh's Sun is AWESOME

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

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 23,051

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.

Offline

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

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

srinithayyil

Offline

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

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?

Offline

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

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.

Offline

**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,653

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

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 23,051

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.

Offline

Pages: **1**