The cone has a height of 15 meters and diameter of 6.5 meters.

Due to similar triangles:

d = 6.5/15 * h

r = 13/60 * h Since radius is half the diameter.

Using the volume equation above.

V = 1/3 * π * r^{2} * h

Substituting r

V = 1/3 * π * (13/60 h)^{2} * h

V = 169πh^{3}/(3600*3)

V = 169πh^{3}/10800

Taking the derivative with respect to time of both sides yields.

dV/dt = 169πh^{2}/3600 * dh/dt

Substitute **h = 150 cm**

dh/dt = 18 cm/min

dV/dt = 59729.5 cm^{3}/min

Since there is an out flow of 8300 cm^{3}/min

The inflow must be dV/dt + outflow.

59729.5+ 8300 = 63,029.5 cm^{3}/min