Question

Find the volume of a cone if the radius of its base is 7 cm and its slant height is 28 cm.

Answer 1

radius=7cm.

slant height=28cm.

height=?

slant height=

$\sqrt{r {}^{2} } + \sqrt{} h {}^{2}$

$28 {}^{2} = 49 + h {}^{2}$

$784 - 49 = h {}^{2}$

$735 = h {}^{2}$

$\sqrt{735 } = h$

27.11=h

Volume of a cone=

$1 \div 3\pi \: r {}^{2} h$

=1/3×22/7×49×27.11

=1391.64(almost)

I hope it will help you...