Find the slant height of the cone shown

Question

Find the slant height of a cone
(to the nearest whole meter) having a radius of 6 m and height of 8 m.

 

Find the volume and the surface area of the above cone rounded to the nearest

tenths.

Answer 1

slant height

6²+8²=(Hs)² where Hs is the slant height

36+64=(Hs)²

100=(Hs)²

Hs=10 m

 

volume

V=(1/3)*pi*r²*h

V=(1/3)*3.14*6²*8

V=(1/3)*3.14*36*8

V=3.14*12*8

V=3.14*96

V=301.44 cubic meters

 

surface area

lateral surface area=(1/2)*circumference*slant height

lateral surface area=(1/2)(2*pi*r)*10

lsa=pi*6*10

lsa=3.14*60

lsa=188.4 sq m

now find the area of the circular base

A=pi*r²

A=3.14*6²

A=3.14*36

A=113.04 sq m

now add the lateral surface area and the area of the base

total surface area=188.4+113.04

total surface area=301.44 sq m