What is the volume of a sphere with a surface area of 9π yd2?

The SA of a sphere is 4 times the area of the base of if you cut it in half. So that would mean that that would be (9/4)pi yd2. Pi*r^2=area of a circle, so that means the radius is 3/2 yds. 
The volume of a sphere is (4/3)*pi*r^3. If we plug in the radius, we get: 
(4/3)*pi*(3/2)^3 
(4/3)*pi*(27/8) 
(27/6)pi, or 4 and 1/2 pi 
If you want an actual number with pi used, you get about 14.137166952