A large dump truck will empty its full load of stone onto a small plot of land for storage. The rock forms a cone that is 9 feet tall. The truck holds 144 cubic feet of stone. What is the area of the circular base of the pile of stones?

Respuesta :

Volume of a cone = (1/3) * Area of Base * height
144 * 3 / 9 = Area of Base
Area of the Base = 48



Answer:

48 square feet.

Step-by-step explanation:

A large dump truck will empty its full load of stone .

Those rock forms a cone.

Height of cone = 9 feet

The truck holds 144 cubic feet of stone.

So, amount of stone truck holds = Volume of cone

Formula of volume of cone = [tex]\frac{1}{3} \pi r^{2} h[/tex]

Where [tex]\pi r^{2} = \text{Area of base }[/tex]

           [tex]h= height[/tex]

So, volume of cone formed  = [tex]\frac{1}{3}\times\text{Area of base}\times 9[/tex]

Since we know that amount of stone truck holds = Volume of cone formed

[tex]144=\frac{1}{3}\times\text{Area of circular base}\times 9[/tex]

[tex]144\times 3=\text{Area of base}\times 9[/tex]

[tex]432=\text{Area of circular base}\times 9[/tex]

[tex]\frac{432}{9}=\text{Area of circular base}[/tex]

[tex]48=\text{Area of circular base}[/tex]

Thus the area of the circular base is 48 square feet.