There is an inverted square pyramid with a height of 10 m. The side of the square is 13 m. Someone decides to fill the pyramid with water, and does so at a rate of 10 m3 per second. How quickly is the water level rising when it reaches the top? I understand I need to find dh/dt, and that dV/dt = dV/dh x dh/dt with dV/dt being 10. In order to find dV/dh I need to express the volume of the pyramid as a function of only h in order to find the derivative. So if the volume of the pyramid is V = (1/3)(b^2)h, how do I express b^2 in terms of h? I realize this might be futile to post this here, but anyone know of a better website for help with math problems like this one?