The height of a cone is 15 cm. If its volume is 1570 cm³, find the radius of the base. (Use π = 3.14)

Solution:

Volume of a cone of base radius 'r', and height 'h' = 1/3πr²h

Volume of the cone = 1570 cm³

Height of the cone, 'h' = 15cm

Radius of the cone, 'r' = ?

1/3πr²h = 1570 cm³

r² = (1570 cm³ × 3) / πh

r² = (1570 cm³ × 3) / (3.14 × 15 cm) = 100 cm²

r = √100 cm²

r = 10 cm

Radius of the base = 10 cm

☛ Check: NCERT Solutions for Class 9 Maths Chapter 13

Video Solution:

The height of a cone is 15 cm. If its volume is 1570 cm³, find the radius of the base. (Use π = 3.14)

NCERT Solutions for Class 9 Maths Chapter 13 Exercise 13.7 Question 3

Summary:

It is given that the height of a cone is 15 cm and the volume of the cone is 1570 cm³. We have found that the radius of the base = 10 cm.

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