Question

The surface of the area of a sphere is 616 sq. Cm. The surface area of its hemishere is

Answer 1

Given :

• Surface Area of Sphere = 616 cm²

To Find :

• Surface Area of Hemisphere

Solution :

In this question Surface Area of Sphere is given and we have to find the Surface Area of Hemisphere. So for that we will find the radius because formula of Surface Area of Hemisphere is 3πr² and formula of Surface Area of Sphere is 4πr² .

Finding the Radius :

• Surface Area of Sphere = 4πr²
• 616 = 4πr²
• 616 = 4 × 22/7 × r²
• 616/4 = 22/7 × r²
• 154 = 22/7 × r²
• 154 × 7 = 22 × r²
• 1078 = 22 × r²
• 1078/22 = r²
• 49 = r²
• √49 = r
• 7cm = radius

Finding Surface Area of Hemisphere :

• Surface Area of Hemisphere = 3πr²
• Surface Area = 3 × 22/7 × (7)²
• Surface Area = 3 × 22/7 × 7 × 7
• Surface Area = 3 × 22 × 7
• Surface Area = 66 × 7
• Surface Area = 462cm²

Therefore :

• Surface Area of Hemisphere is 462cm²

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Answer 2

Good morning my dear friend, here is the answer to your question..

Given,

surface area of sphere = 616 cm²

4πr² = 616

4 × 22/7 × r² = 616

88/7 ×r² =616

r² = 616 × 7 / 88

r² = 49

r = 7 cm

Surface area of hemisphere = 3πr²

Therefore,

= 3 × 22/7 × 7²

= 3 ×22 ×7

= 462 cm²