Question

A cone of height 20cm and base radius 15cm. Calculate the slant height . Calculate the curved surface area ​

Answer 1

A cone of height 20cm and base radius 15cm. Calculate the slant height . Calculate the curved surface area.

Height = 20 cm

Radius = 15 cm

$\mathtt{ {l}^{2} = {h}^{2} + {r}^{2} } \\ \\ \implies\mathtt{ {l}^{2} = {20}^{2} + {15}^{2} } \\ \\ \implies\mathtt{ {l}^{2} = 400 +225 } \\ \\ \implies\mathtt{ {l}^{2} = 625 } \\ \\ \implies\mathtt{ {l} = \sqrt{625} } \\ \\ \implies\mathtt{l = 25 \: \: ans}$