The height of a cone is two times its base diameter. What is the volume of the cone in terms of its base radius r?

Question

mathstudent55 · Answer

Do you know the formula of the volume of a cone?

anonymous · Answer

what are the choices?

anonymous · Answer

v = π r 2 h 3

mathstudent55 · Answer

is there a fraction there? Is there an exponent there?

anonymous · Answer

A. V= 2/3 PIE R2
B. V= 4/3 PIE R3
C. V= 1/3 PIE R3
D. V= 1/3 PIE R2

mathstudent55 · Answer

Do you mean this for the formula?

$\LARGE V_{cone} = \dfrac{\pi r^2 h}{3}$

anonymous · Answer

YEAH

mathstudent55 · Answer

Great. That is the correct formula.
Notice the formula uses r to mean radius of the base, and h to mean the height of the cone.

mathstudent55 · Answer

Now let's look at your problem's cone.
The radius is r.
What is the diameter, d, compared to the radius?

mathstudent55 · Answer

In any circle, what is the relationship between the diameter and the radius?

mathstudent55 · Answer

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