Originally Posted by

**maximade** The Question is:

Water drains from the conical tank shown in the figure at the rate of 5ft^3/min.

How fast is the water level dropping from when h=6ft?

ok the relation between the variables h and r is: 5r/2=h

And i know the answer to the question is .276 ft/min, but i don't know how you get that.

What i did was do the derivative of the cone volume formula: (1/3)pi(r^2)h using the product rule and i differentiate the h as well. Plus i even substitute r with 2h/5 (since i want to know r in terms of h) after that i replace everything with the appropriate numbers and my answer is different. Can you guys show me how to do this step by step? Thank you.