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# Find the surface area of a sphere of radius:

i) 10.5 cm ii) 5.6 cm iii) 14 cm

**Solution:**

i) Radius, r = 10.5cm

Surface area of the sphere = 4πr^{2}

= 4 × 22/7 × (10.5cm)^{2}

= 1386 cm^{2}

ii) Radius, r = 5.6cm

Surface area of the sphere = 4πr^{2}

= 4 × 22/7 × (5.6cm)^{2}

= 394.24 cm^{2}

iii) Radius, r = 14cm

Surface area of the sphere = 4πr^{2}

= 4 × 22/7 × (14cm)^{2}

= 2464 cm^{2}

Thus, the surface areas of the sphere of radii 10.5 cm, 5.6 cm, and 14 cm are 1386 cm^{2}, 394.24 cm^{2}, and 2464 cm^{2} respectively.

**☛ Check: **NCERT Solutions for Class 9 Maths Chapter 13

**Video Solution:**

## Find the surface area of a sphere of radius: i) 10.5 cm ii) 5.6 cm iii) 14 cm

Class 9 Maths NCERT Solutions Chapter 13 Exercise 13.4 Question 1

**Summary:**

The surface areas of the sphere of radii 10.5 cm, 5.6 cm, and 14 cm are 1386 cm^{2}, 394.24 cm^{2}, and 2464 cm^{2} respectively.

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