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The height of a right circular cone is 30 cm. A small cone is cut off from the top by a plane parallel to the base of the cone. If the volume of the s
Question



The height of a right circular cone is 30 cm. A small cone is cut off from the top by a plane parallel to the base of the cone. If the volume of the small cone is ​127\frac{1}{27}​ of the volume of the given cone, then at what height above the base was the cone cut?

A.

10 cm

B.

15 cm

C.

20 cm

D.

18 cm

Correct option is C

Let:
H = 30 cm (Height of the original cone)
h = Height of the small cone
V_small / V_large = (h/H)³ = 1/27
(h / 30)³ = 1/27
Step 2: Solving for h
Taking the cube root on both sides:
(h / 30) = 1/3
h = 30 × 1/3 = 10 cm
Thus, the small cone has a height of 10 cm, meaning it was cut at:
Height from the base = 30 - 10 = 20 cm.

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