Question

If volume of a sphere is increased by 72.8% then by what % its surface area will increase?

Answer 1

Help me...

Answer 2

consider
sa = v
r^2 = r^3
if v is increased by 72.8, then R= cube root under 1.728r
so sa= R^2 = (cube root under 1.728r)^2 = 1.44r
thus surface area will increase by 44%

Answer 3

saruz ! if sa = v then how r^2 = r^3 because sa = 4 pie r^2 and v = 4/3 pie r^3

Answer 4

saruz reply soon.....

Answer 5

that is not true at all ........that is the thing you need to do in rough.....its just a fast method of doing mathematics.....
sa never = v
but sa (three equal to sign) v

Answer 6

that is an assumption!

Answer 7

did i get the answer wrong?>

Answer 8

your ans. is right but after assumption when we equal sa and v then
(see fig.)