A spherical balloon is blown up so that it's volume increases constantly at the rate of 2cm^3 per second .find the rate of the increase of the radius when the volume of the balloon is 50cm^3

Answer 1

v = 4/3 πr^3
dv/dt = 4πr^2 dr/dt
so now, determine r when v = 50, and then plug in your numbers to find dr/dt.