If the volume of a sphere is numerically equal to its surface area, then find the diameter of the sphere. -Maths 9th

If the volume of a sphere is numerically equal to its surface area, then find the diameter of the sphere. -Maths 9th
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Answer :

Let r be the radius of the sphere.  and Volume of a sphere = surface area of the sphere  ⇒ 4 / 3πr3 = 4πr2 ⇒ r = 3 cm  ∴ Diameter of the sphere = 2r = 2 × 3 = 6 cm
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