# Find the radius of a sphere whose surface area is 154 cm^{2}.

**Solution:**

Given: The surface area of a sphere is 154 cm^{2}.

The surface area of the sphere of radius r, SA = 4πr^{2}.

The surface area of the sphere = 154 cm^{2}

4πr^{2} = 154 cm^{2}

r^{2} = 154/4π

r^{2} = (154/4) (7/22)

r^{2} = (154 × 7) / (4 × 22)

r^{2} = (49/4)

r = (7/2) = 3.5 cm

Thus, the radius of the sphere whose surface area is 154 cm^{2} is 3.5 cm.

**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 cm^{2 }is equal to 3.5 cm.