Page 223 Problem 15 Jordan Weinberg
The Problem A spherical balloon is to be deflated so that its radius decreases at a constant rate of 15cm/min.  At what rate must air be removed when the radius is 9cm.
Given Solution Volume of a sphere: 4/3 Π  r^3 dr/dt=15 r=9
Step by Step Solution dv/dt=  4/3 Π  r^3
Step by Step Solution dv/dt=  4/3 Π  * 3r^2(dr/dt)
Step by Step Solution dv/dt= 4/3 Π  * 3(81) (15)
Step by Step Solution dv/dt= 4860 Π  cm^3/min

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