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**∞****Guest**

I was just curious, what is the formula for the surface area and volume,

and respectively, for a pyramidal frustum and a conical frustum? I would prefer you to put it in LaTeX so I can easily understand it. Thanks!Note: later I may ask for other formulas, so don't put away your brain when you're done!

**∞****Guest**

Oops, I almost forgot; I would also like a picture showing where the demensions are. Thanks...again!

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,882

Hi;

For a right pyramidal frustum:

Look here for more:

http://mathworld.wolfram.com/PyramidalFrustum.html

*Last edited by bobbym (2013-03-06 21:11:26)*

**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.**

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**∞****Guest**

Thanks!

I do want to ask though, is a right frustum just a straight, generic one? Or is it one that is tilted?

Also, I checked out the link, and it seems that the full surface area (as in, the whole surface of it including bases) is:

Am I right? I am kind of confused. The volume formula though, is easy for me to understand.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,882

Hi;

It is much better to write it like this:

check out this url:

**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.**

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**∞****Guest**

Sorry I wrote that wrong.

Thanks, again; I think I now understand it. (:

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,882

Hi;

Okay, you are welcome.

**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.**

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**∞****Guest**

Next geometry question I've been wondering:

What is the perimeter

I was thinking it was where is the larger radius, but what about the inner part?

Is that included in the formla, or is it just the 'strict' outside?

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,882

Hi;

The perimeter of an annulus is the sum of the perimeter of the two circles, interior and exterior.

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

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**∞****Guest**

6 more (these might be tougher than before):

1. A & P of a Lune of Hippocrates.

2. V & S of spherical cap.

3. V & S of a spherical sector.

4. V & S of a spherical segment.

5. V & S of a spherical shell.

6. V & S of a spherical wedge.

Where V = volume, S = surface area, A = area, P = perimeter.

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,882

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

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