If the volumes of two cones are in the ratio of 1 : 4 and their diameters are in the ratio of 4 : 5, find the ratio of their heights.
Let V1 be the volume of first cone and V2 be the volume of second cone.
Then, V1:V2 = 1:4
Let d1 be the diameter of first cone and d2 be the diameter of second cone.
Then d1:d2 = 4:5
Let h1 be the height of first cone and h2 be the height of second cone.
We know that volume of cone is given by V = 1/3 × π(d2/4)h
∴
⇒
⇒
⇒
⇒
∴ h1:h2 = 25:64
∴ Ratio of height of two cones is 25:64.