Question

If the volume of a right circular cone of height 9 cm is 48π cm3, find the diameter of its base.

Answer 1

Height (h) of cone = 9 cm
Let the radius of the cone be r.
Volume of the cone = 48$\pi$ cm³
$\frac{1}{3}\pi$r²h = 48π cm³

r² =$\frac{ 48 \ cm^3 × 3 }{ h}$

r² = $\frac{48\ cm^3 × 3 }{ 9\ cm}$
r² = 16 cm²
r = $\sqrt{16}$ cm²
r = 4 cm

Diameter of base d = 2 × radius(r)
= 2 × 4 cm
= 8 cm