Find the radius of a sphere whose surface area is 154 cm².

Solution:

Given: The surface area of a sphere is 154 cm².

The surface area of the sphere of radius r, SA = 4πr².

The surface area of the sphere = 154 cm²

4πr² = 154 cm²

r² = 154/4π

r² = (154/4) (7/22)

r² = (154 × 7) / (4 × 22)

r² = (49/4)

r = (7/2) = 3.5 cm

Thus, the radius of the sphere whose surface area is 154 cm² is 3.5 cm.

☛ Check: Class 9 Maths NCERT Solutions Chapter 13

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Video Solution:

Find the radius of a sphere whose surface area is 154 cm².

Class 9 Maths NCERT Solutions Chapter 13 Exercise 13.4 Question 6

Summary:

The radius of a sphere whose surface area is 154 cm² is equal to 3.5 cm.

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