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Class 10 math (India)

Course: Class 10 math (India) > Unit 12

Lesson 3: Frustum of a cone
Math
Class 10 math (India)
Surface areas and volumes
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 15, start text, c, m, end text and base radius 25, start text, c, m, end text, a cone of height 6, start text, c, m, end text 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, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
start text, c, m, end text
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