Last updated at May 29, 2018 by Teachoo

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Ex 13.7, 6 The volume of a right circular cone is 9856 cm3. If the diameter of the base is 28 cm, find height of the cone Radius of cone = r = = cm = 14 cm Let Height of cone = h cm Volume of the cone = 9856 cm3 πr2h = 9856 = 9856 h = ∴ h = 48 Thus, the height of the cone = 48 cm. Ex 13.7, 6 (ii) slant height of the cone Here, r = 14 m and h = 48 cm Let slant height be l We know that l2 = r2 + h2 l2 = l2 = l2 = l = l = l = 50 cm Thus, the slant height of the cone = 50 cm. Ex 13.7, 6 (iii) curved surface area of the cone We know that, r = 14 m and = 50 cm. Curved surface area = πr = cm2 = cm2 = 2200 cm2

Example 2
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Ex 13.1, 6 Important

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Example 6 Important

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Example 14 Important

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Ex 13.7, 6 Important You are here

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Example 18 Important

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Surface Area and Volume Formulas Important

Class 9

Important Questions for Exam - Class 9

- Chapter 1 Class 9 Number Systems
- Chapter 2 Class 9 Polynomials
- Chapter 3 Class 9 Coordinate Geometry
- Chapter 4 Class 9 Linear Equations in Two Variables
- Chapter 5 Class 9 Introduction to Euclid's Geometry
- Chapter 6 Class 9 Lines and Angles
- Chapter 7 Class 9 Triangles
- Chapter 8 Class 9 Quadrilaterals
- Chapter 9 Class 9 Areas of parallelograms and Triangles
- Chapter 10 Class 9 Circles
- Chapter 11 Class 9 Constructions
- Chapter 12 Class 9 Herons Formula
- Chapter 13 Class 9 Surface Areas and Volumes
- Chapter 14 Class 9 Statistics
- Chapter 15 Class 9 Probability

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.