Question 1186789
A spherical balloon is inflated with gas at a rate of 900 cubic centimeters per minute.

(a) How fast is the radius of the balloon changing at the instant the radius is 60 centimeters?
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{{{V = 4*pi*r^3/3}}}
{{{dV/dt = 4*pi*r^2*(dr/dt) = 900}}}
{{{dr/dt = 900/(4*pi*r^2)}}}
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(b) How fast is the radius of the balloon changing at the instant the radius is 90 centimeters?
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Same as (a), different numbers