Question

How many spheres 12 cm in diameter can be made from a metallic cylinder of diameter 8 cm and height 90 cm?

Answer 1

Vol of cylinder = $x\times volumeofsphere$
$\pi$$r^2$h = x $\times$$\frac{4}{3}$$\pi$$R^3$
$\left(\frac{4^2}{9}\right)$ = x $\times$ $\frac{4}{3}$$\frac{22}{7}$ $\times$ $6\times 6\times 6$
16 $\times$ 90 = x $\times$ 4$\times$2$\times$6$\times$6
$\left(\frac{16\times 90}{4\times 2\times 6\times 6}\right)$ = x
x = 5
5 spheres can be made out of this cylinder