Question

If a sphere and a cube have equal surface areasareas then the ratio of the diameter of sphere to the edge of cube is

Answer 1

S.A of cube = S.A of sphere

4 pi r^2 = 6 a^2

2 pi (d/2)^2 = 3 a^2

2 pi d^2 /4 = 3 a^2

Pi d^2 / 2 = 3 a^2

d^2 / a^2 = 3*2 / pi

(d/a)^2 = 6 *7 /22

d/a = underoot 21 / underoot 11

It would be simpler if c.s.a of cube was equal.