The volume of a cylinder is 54 π cm3. If the radius is 3 cm, what is the height of the cylinder?

An image displaying a cylinder of radius 3 centimetre and volume equals 54 pi cubic centimetre.
A.
18 cm
B.
9 cm
C.
3 cm
D.
6 cm

1 answer

To find the height of the cylinder, we can use the formula for the volume of a cylinder:

\[ V = \pi r^2 h \]

where \( V \) is the volume, \( r \) is the radius, and \( h \) is the height.

Given:

  • \( V = 54\pi , \text{cm}^3 \)
  • \( r = 3 , \text{cm} \)

We can substitute the values into the volume formula:

\[ 54\pi = \pi (3)^2 h \]

Simplifying this, we find:

\[ 54\pi = \pi (9) h \]

Now, divide both sides by \( \pi \):

\[ 54 = 9h \]

Next, solve for \( h \):

\[ h = \frac{54}{9} = 6 , \text{cm} \]

Therefore, the height of the cylinder is:

\[ \boxed{6 , \text{cm}} \]

So the answer is D. 6 cm.