Asked by Daniel

A spherical balloon expands uniformly as it is inflated. The radius of the balloon in r meters at time t seconds. Find the radius, the volume, and the surface area of the balloon when the rates of increase of the surface area of the balloon and the radius are numerically equal
Answered by Steve
da/dt = 8πr dr/dt
If da/dt = dr/dt, then r = 1/8π

so, now you can find the area and volume.
Answered by Student
Steve, what is dr/dt? how did you get 1/8pi?