Pi r^2xh

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volume of a cylinder
Pi r^2xh
which one first?

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@dadpad,

PEMDAS

PArenthesis come first (you don't have any)
Exponents come second (radius squared)
Multiplication and Division come next, from left to right (Pi x your product of rad sq x height)

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@littlek,

thanks K
now a test for you

Its not propely a cylinder

Its more like a cone with the top cut off.
How can I calculate a volume?

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@dadpad,

dadpad wrote:

a cone with the top cut off.
How can I calculate a volume?

V = 1/3 * pi * (R1^2 + R1 * R2 + R2^2) * h
R1 = Radius of the base
R2 = Radius of the top
h = height of the truncated cone

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@dadpad,

I'm not sure I get the image, is it a straight up cone ? Then your above formula dived by 3 would work. Otherwise (if it has two blunt ends) go with contrex's formula.

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Thanks contrex.

does this work?
r1 + r2 + r3 /3 = avg r
pi (avgr)^2 x H

lil K shape is similar to this. wider at base than top but top is not a point
.......... /\ ........

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@dadpad,

no. At least your formula does not equate to contrex's formula.

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@contrex,

V = 1/3 * pi * (R1^2 + R1 * R2 + R2^2) * h

or put another way...

The volume of a circular cone frustum (a cone with the apex sliced off parallel with the base) is

$http://upload.wikimedia.org/math/0/3/5/035329cf00942725a35baee2f417bdc2.png$

http://en.wikipedia.org/wiki/Frustum

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Pi r^2xh

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