Q6 of 75 Page 225

Find the radius of a sphere whose surface area is 154 cm2

Let the radius of the sphere be r

Surface area of sphere = 154 cm2


4r2 = 154


r2 = () cm2


= () cm2


r = () cm


= 3.5 cm


Therefore, the radius of the sphere whose surface area is 154 cm2 is 3.5 cm


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