Volume of a cone help please

Question

A special stainless steel cone sits on top of a cable television antenna. The cost of the stainless steel is $8.00 per cubic centimeter. The cone has radius 12 cm and height 20 cm. What is the cost of the stainless steel needed to make this solid steel cone? Use 3.14 for pi.

Answer 1

The volume of a cone is V_cone = pi × r² × (h/3)

 

So V_cone = 3.14 x (12cm)² x (20cm/3) = 3014.4 cm³

 

The cost of stainless steel is  $8.00/cm³ 

 

So the total cost of the stainless steel needed to fill the volume of this cone is:

 

($8.00/cm³) x 3014.4 cm³ = $24,115.20