If a balloon is in the shape of a sphere and has a surface area of pi/9 ft^2, what is the length of the radius?
+1491 The surface area of a sphere is equivilent to A = 4πr^2.
All you need to do is plug in (π/9) for A and solve for r.
(π/9) = 4πr^2
Divide 4 on both sides:
(π/36) = πr^2
Divide π on both sies:
(1/36) = r^2
Take the square root of both sides:
1/6 = r
Use appropiate units and get...
Radius = 1/6 feet
Hope this helps. c:
