Question 92944
Hi,<br />

First things first, you need to know the formula for the volume of a cone is *[tex \frac{1}{3}\pi r^2h] Which, as the question says is a third the volume of a cylinder.<br />

We need to know the volume when the water is at height h. So this means for a given h, we need to figure out r.<br />

By the definition of a cone, for any point on the cone's surface (apart from the tip) the ratio of r and h is constant. To understand that, think of a cone as a line in the x-y plane rotated about the x axis. The ratio of r and h is simply the gradient of that line.<br />

So *[tex r/h=10/38]. Substituting this in to the formula for the volume of a cone gives:<br />

*[tex V=\frac{25}{1083}h^3]<br />

Kev