A hollow sphere has a volume of kcm3 and a surface area of kcm2. Calculate the diameter of the sphere.
-
A.
3cm -
B.
6cm -
C.
9cm -
D.
12cm -
E.
More information is needed
Correct Answer: Option B
Explanation
(Volume = frac{4}{3} pi r^3 = k) …(i)
(S.A = 4pi r^2 = k) … (ii)
Divide (i) by (ii),
(frac{4}{3} pi r^3 div 4pi r^2 = frac{k}{k})
(frac{r}{3} = 1 implies r = 3cm)
Diameter = 2 x 3cm = 6cm