Question

264m²canvas is required to build a conical tent .if the slant height of the cone is 12m,find its vertical height

Answer 1

Area of canvas used=
$264m {}^{2}$
C.S.A of cone=
$264 m{}^{2}$
now, 264=πrl = 264=22/7×r×12
= (264×7)÷22×12 =r
therefore r=7m
Now, by Pythagoras therorem,
$h { }^{2} + r {}^{2} = l {}^{2}$
$h {}^{2} = 12 {}^{2} - 7 {}^{2}$
$h {}^{2} = 144 - 49$
$h {}^{2} =95$

h=9.75