(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Sand is falling into a conical pile at a rate of 10 cubic feet/minute. The diameter of the cone is 3 times the altitude. At what rate is the height of the pile change when the height=15feet.

So i was going through and I dont know if i derived it wrong, but i had

v=1/3pi(r^2)h

so

dv/dt= pi/3 R[tex]^{2}[/tex](dh/dt) * 2pi/3 R (h)

but when i go through and solve it all with R= 3/2h I dont get the answer form the back of the book. Is my derivative wrong? I used chain rule...

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# Homework Help: Rates of change

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