Answer:
The area that will be painted grey is
.
Step-by-step explanation:
Given:
Circumference of the free-throw circle= 30.77 feet
we need to find the area that will be painted grey.
Solution:
First we will find the radius (r).
Now we know that circumference of the circle is 2 times π times radius (r).
Framing in equation form we get;

Dividing both side by 2π we get;

Now given:
A basketball team wants to paint half of a free-throw circle grey.
So we will use the formula for semicircle.
Area of semicircle is half times π times square of the radius (r).
framing in equation form we get;
area that will be painted grey = 
Rounding to nearest foot we get;
area that will be painted grey = 
Hence The area that will be painted grey is
.