Acone has a volume of 5 cubic inches. what is the volume of a cylinder that the cone fits exactly inside of?
15 in3
20 in3
25 in3
30 in3

The answer is 15 in³.

The volume of the cone is:

where:
V₁ - the volume of the cone
r₁ - the radius of the cone
h₁ - the height of the cone

The volume of the cylinder is:

where:
V₂ - the volume of the cone
r₂ - the radius of the cone
h₂ - the height of the cone

Since the cone fits exactly inside of the cylinder, they have the same radius and the height:
r₁ = r₂
h₁ = h₂

Also:
V₁ = 5

Now, let's write two volume formulas together:



We can include V₂ into V₁:


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