A conical water tank with vertex down has a radius of 15 feet at the top and is 28 feet high. If water flows into the tank at a rate of 20 ft3/min, how fast is the depth of the water increasing when the water is 14 feet deep?
The depth of the water is increasing at_____ ft/min.

Question

A conical water tank with vertex down has a radius of 15 feet at the top and is 28 feet high. If water flows into the tank at a rate of 20 ft3/min, how fast is the depth of the water increasing when the water is 14 feet deep?
The depth of the water is increasing at_____  ft/min.

phi · Answer

First step is write down a formula for the volume of the conical tank

phi · Answer

The other idea you need is to use similar triangles
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phi · Answer

This might be helpful. See example 4 http://tutorial.math.lamar.edu/Classes/CalcI/RelatedRates.aspx

anonymous · Answer

thank you so much !!!!

phi · Answer

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