Surface of a sphere=4πr²
Data:
Surface=200 ft²
4πr²=200 ft²
We have to find the radius when we start to inflate
r₁=√(200 /4π) ft=√(50/π) ft
if the original radius is doubled, this radius will be:
r₂=2√(50/π) ft
And the new surface would be:
New surface=4π(2√50/π)²=800 ft²
Answer: 800 ft²
