Selim is ordering concrete spheres to place as barriers in the city park. The spheres cost $2 per square foot, and Selim can spend $20 per sphere. What is the maximum diameter of the spheres he can purchase?

Respuesta :

Answer:

1.78 feet.

Step-by-step explanation:

If they cost $20 each and its $2 per square foot, the area of the spheres

is 20 / 2 = 10 ft^2.

Area of sphere = 4 π r^2 = 10   (where r = the radius)

---> r^2 = 10 / 4π

            =   0.796

---> r = 0.892 ft

So the diameter = 2 * r  

                           =  1.78 feet to nearest hundredth.