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I need help please. A cone with a height of 15 mm has a volume of approximately 15.7 mm cubed. To the nearest whole number, what is the diameter of the cone?

User Megs
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1 Answer

21 votes
21 votes

The volume formula for a circular cone is


V=(1)/(3)\pi(r)^2h

Where h = 15 and V = 15.7, let's replace this information and solve for r


\begin{gathered} 15.7=(1)/(3)\cdot\pi\cdot(r)^2\cdot15 \\ 15.7=15.71r^2 \\ r=\sqrt[]{(15.7)/(15.71)} \\ r\approx1 \end{gathered}

If the radius is 1 mm, then the diameter is 2 because it must be double.

Hence, the diameter measures 2 mm.

User Yury Finchenko
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