Q. 16 E4.3( 22 Votes )
If the length of radius of a sphere is increased by 50%, let us write how much percent will be increased of its curved surface area.
Let the initial radius be r.
After 50% increase, new radius r’ = r+0.5r = 1.5r
Initial Surface area = 4×π×r2
Final Surface Area = 4×π×(1.5r)2 = 9×π×r2
⇒ Percent increase =
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