I have a calculus question and was wondering if some could help me see what I am doing wrong in this question. Thank you(adsbygoogle = window.adsbygoogle || []).push({});

A conical tank with an altitude of 10m and whose base has a radius of 4m is mounted with its vertex down. The tank is full of water which is draining through the vertex at the rate of 5 m^3/min. how fast is the level of the water dropping when the radius is 3?

the answer is 5pi/9

this is how i did it:

r/h=4/10

h=5pi/2

V=[(pi)(r^2)(h)]/3

V=[(pi)(r^2)(5r/2)]/3

V=[pi5r^3]/6

dv/dt=[15pi(r^2)]/6] * dr/dt

5=[(15pi(3^2)]/6] * dr/dt

dr/dt= (2pi)/9

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# Homework Help: Conical tank calc help

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