Question

The total surface area of two hemisphere are in ratio of 16:36 . Find the ratio of their radius.

Answer 1

let the radius of first hemisphere be
' r1 'and
radius of second hemisphere be ' r2 '

now TSA of first hemisphere=2πr1^2

andTSA of second hemisphere=2πr2^2

since the ratio of their areas = 16/36

according to question,

2πr1^2 : 2πr2^2 = 16 : 36

r1^2 : r2^2 = 16: 36

r1^2 / r2^2 = 16 / 36

r1 / r2 = √(16/36 )

r1 / r2 = 4 / 6

r1 / r2 = 2 / 3

r1 : r2 = 2: 3

therefore ,ratio their radius = 2 : 3
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Your Answer r1 : r2 = 2 : 3
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