Question
The cross sectional area of a hemisphere is 2772 cm²
and its volume is 19404 cm³. What is its radius?Solution
As we know, Volume of hemisphere = (2/3) πr3 (2/3) πr³ = 19404 --- (1) The curved surface area of the hemisphere = 2 πr² 2 πr² = 2772      …  (2) Dividing (1) by (2),  [(2/3) πr³]/ [2 πr²] = 19404/2772  r/3 = 7 r = 21 cm
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