Question

A right circular cone of hight 24 cm has volumes 616 cm cube find the area of its curved surface

Answer 1

$v = {\pi}{r}^{2} h \\ 616 = \ \frac{22}{7} {r}^{2} \times 24 \\ \frac{616 \times 7}{22 \times 24} = {r}^{2} \\ \frac{49}{6} = {r}^{2} \\ r = \sqrt{ \frac{49}{6} } = \frac{7}{ \sqrt{6} } = \ \: \frac{7 \sqrt{6} }{6} \\ \\ \\ csa = 2\pi \: rh \\ = \frac{2 \times 22 \times 7 \sqrt{6} \times 24}{6} \\ = 1232 \sqrt{6} {cm}^{2}$