If the volume of a cylinder is 81 what is the volume of a cone that fits perfectly inside

Your answer would be 27.

This is because the formula for the volume of a cylinder is πr² × h, and the formula for a cone is 1/3 × (πr² × h), which we can also write as (πr² × h)/3.

This means that a cone that fits perfectly inside a cylinder will have a volume that is 1/3 the volume of the cylinder. Thus, 81 ÷ 3 = 27.

I hope this helps!