A cone with a radius of 3" has a total area of 24 sq. in. Find the volume of the cone.
Solution:
Given: radius of the cone = 3 in
The total Surface area of the cone = 24 sq.in
We know that the volume of the cone is 1/ 3 πr2h.
We will first find the height of the cone using the total area.
Total Surface area = Area of the circular base + area of the curved surface
TSA = πrl + π r2
24 - 9 π = πrl
πrl = 15π [Area of the remaining curved surface]
π (3) l = 15π
Divide both sides by 3π.
l = 5.
l2 = h2 + r2
h= 25 - 9
h2 = 16
h = 4
Using the value of h in the volume of cone 1/ 3 πr2h.
Volume = 1/ 3 × 22/ 7 × 9 × 4
= 264/ 7
= 37.71 in3
A cone with a radius of 3" has a total area of 24 sq. in. Find the volume of the cone.
Summary:
The volume of the cone with a radius of 3 in has a total area of 24 sq. in is 37.71 in3.
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