Question 1083348
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What is the volume of a frustum of a cone with a height of 6 inches, a top diameter of 8 inches and a bottom diameter of 16 inches? 
Round to the nearest whole number.
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The diameter (and the radius) of the cone decrease in 2 times when the height changed in 6 inches. 

It means that the total height of the entire/whole/full cone is 12 inches.


It should be clear to you.
If it is not clear, make a sketch and mark the dimensions.


Now the volume of the frustum cone is the difference between the volume of the full cone and the volume of its upper (cut) part:

{{{(1/3)*pi*(16/2)^2*12 - (1/3)*pi*(8/2)^2*6}}} = {{{(pi/3)*(8^2*12 - 4^2*6)}}} = {{{(pi/3)*672}}} = {{{224*pi}}}.


To check my result, I will use the formula for the volume of the cone frustum from Wikipedia 

V = {{{((pi*h)/3)*(R^2 + rR + r^2)}}} = {{{((pi*6)/3)*(8^2 +8*4+4^2)}}} = {{{224*pi}}}.


The solution (the solutions) is/are correct.
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Writing by "josgarithmetic" is TOTALLY WRONG.


Simply ignore it for your safety.