Mathematics

Problem

A conical tank has a height of 12 m and a base radius of 3 m. At a certain time the water in the tank forms a smaller cone of height

h

meters and surface radius

r

meters. Which of the following relations between

r

and

h

must hold at every instant? a)

r=\dfrac{h}{6}

r=\dfrac{h}{4}

r=\dfrac{h^{2}}{12}

r=\dfrac{h}{3}