A solid consists of a cone on top of a cylinder with a radius equal to that of the cone. The height of the cone is $9$ and the height of the cylinder is $12$ . If the volume of the solid is $45 pi$ , what is the area of the base of the cylinder?

Question

1250 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-05-10T10:18:09

The area is $=9.4u^2$

Let $a=$ area of the base

Volume of cone is $V_(co)=1/3*a*h_(co)$

Volume of cylinder is $V_(cy)=a*h_(cy)$

Total volume

$V=V_(co)+V_(cy)$

$V=1/3ah_(co)+ah_(cy)$

$45pi=a(1/3*9+12)$

$45pi=a*15$

$a=45/15pi$

$a=3pi$

$a=9.4u^2$

A solid consists of a cone on top of a cylinder with a radius equal to that of the cone. The height of the cone is 9 9 and the height of the cylinder is 12 12 . If the volume of the solid is 45 pi45 pi, what is the area of the base of the cylinder?