[SOLVED] Rate of Change - Just checking 1. The problem statement, all variables and given/known data Sand is poured into a conical pile with the height of the pile equaling the diameter of the pile. If the sand is poured at a constant rate of 5m^3/s at what rate is the height of the pile increasing when height is 2 meters. 2. Relevant equations v = [tex](1/3)\pi r^2[/tex] r' = h' / 2 (i think this is right - not sure) 3. The attempt at a solution So i got v' = [tex](1/3)\pi (2rr'h + r^2h')[/tex] So i have 2 unknowns r' and h'. Since we can make the connection that r' = h'/2 i replace that in the equation and get: v' = [tex](1/3)\pi (2r(h'/2)h + r^2h')[/tex] -> r = 1 h = 2 SO: v' = [tex](1/3)\pi (2h' + h')[/tex] -> h' = [tex]5/\pi[/tex] Im not sure if this answer is right but if you can please check over my work, i would appreciate it. Thanks!