Mmmmm...after an internet search.....I found that an NBA ball has a circumference of 29.5 in
So....to find the radius we have
29.5 / [2pi] ≈ 4.695 in = radius
So.....the surface area =
4 * pi * radius^2 =
4 * pi * ( 4.695)^2 ≈ 277 in^2
CPhill, your calculations seem accurate, but why is the answer 277in^2?
The circumference is 29.5 inches (You can memorize this)
Therefore, the diameter would be around 9.4 inches, which makes the radius about 4.7 inches.
The surface area would be around 277.59 in^2, or 278 in^2. I think you had a rounding mistake, CPhill!
Hope this helped!