Math Is Fun Forum

Stefani

Member

Registered: 2009-04-29

Posts: 3

Volume of a Cylinder: Help?

There's this cylinder that I have to calculate the volume of, but it's not a complete cylinder.

It has a radius of 7cm and a height of 16 cm. However, there's a chunk of the cylinder missing, and the angle of this chunk is 120 degrees. Just imagine a cylinder cut into three thirds, but one third is missing, so that the cylinder is only 240 degrees instead of 360 degrees.

I'm not sure if I'm making sense here, but I tried to calculate it and the answer I got was 2463.90 cm cubed. Now, when I look in the answers section to check my answer, it says that the right solution is 2461.76 cm cubed... What am I doing wrong?

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Volume of a Cylinder: Help?

Hi Stefani;

The volume of the whole cylinder is:

You have a wedge cut out of it of 120° That is 1 / 3 of it. So your formula for the volume is:

Last edited by bobbym (2009-10-29 19:11:16)

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