The radius of a cone can be found using the formula [tex]r=\sqrt{\frac{V}{\pi h}}[/tex], where [tex]V[/tex] stands for the volume of the cone and [tex]h[/tex] stands for the height. If [tex]r=4[/tex], [tex]h=8[/tex], and [tex]\pi[/tex] is 3.14, find the volume ([tex]V[/tex]). Round the answer to the nearest hundredths place.

A. 66.99 cubic units
B. 3,365.41 cubic units
C. 133.97 cubic units
D. 33.49 cubic units



Answer :

Let's solve the problem step by step, given the known values: radius [tex]\( r = 4 \)[/tex] units, height [tex]\( h = 8 \)[/tex] units, and [tex]\(\pi = 3.14\)[/tex].

We need to find the volume [tex]\( V \)[/tex] of a cone. The formula for the volume of a cone is:

[tex]\[ V = \frac{1}{3} \pi r^2 h \][/tex]

Substitute the given values into the formula:

1. Square the radius:

[tex]\[ r^2 = 4^2 = 16 \][/tex]

2. Multiply this result by the height:

[tex]\[ r^2 \times h = 16 \times 8 = 128 \][/tex]

3. Multiply this result by [tex]\(\pi\)[/tex]:

[tex]\[ \pi \times 128 = 3.14 \times 128 = 401.92 \][/tex]

4. Finally, multiply by [tex]\(\frac{1}{3}\)[/tex] to get the volume:

[tex]\[ V = \frac{1}{3} \times 401.92 = 133.97 \][/tex]

So, the volume of the cone, rounded to the nearest hundredths place, is 133.97 cubic units. This matches one of the given options:

- 133.97 cubic units

Thus, the correct answer is 133.97 cubic units.