Question
The ratio of the radii of the
bases of a cylinder and a cone is 7:8, while the ratio of their heights is 4:5. What is the ratio of the volume of the cylinder to the volume of the cone?Solution
ATQ,
Let r and R be the radii of the bases of the cylinder and the cone, respectively. r/R =7/8 Let h and H be the heights of the cylinder and the cone, respectively. h/H =4/5 The formula for volume ratio: Substituting values:
Hence, the ratio of the volumes is 147:80.
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