Q17 of 79 Page 229

If the curved surface area of a solid hemisphere is 2772 sq.cm, then find its total surface area.

Given : CSA of hemisphere = 2772 sq.cm

To find : TSA of hemisphere = ?


Formula : CSA of hemisphere = 2r2


TSA of hemisphere = r2


Solution : CSA of hemisphere = 2r2


⇒ 2r2 = 2772


2 × × r2 = 2772


⇒ r2 = = 441


⇒ r = 21 cm


TSA of hemisphere = r2 = 3 × × 21 × 21 = 4158 cm2


∴ The total surface area of the solid hemisphere is 4158 cm2.


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