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Course: Class 10 > Unit 11

Lesson 3: Frustum of a cone
Math
Class 10
Surface area and volume
Frustum of a cone
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Finding dimensions of a frustum using similar triangles

Google Classroom

Problem

From the top of a cone of height 15cm and base radius 25cm, a cone of height 6cm is cut to form a frustum.
What is the radius of the smaller cone?
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
cm