Question 154402
I need to find the surface area of a Christmas tree I made for my summer project. The cone shape is 22 inches tall and has a diameter of 7.5 inches. There is also a base for the cone shape. I also have a cylinder shape for the tree trunk which is 3 inches in diameter and 5 inches in height. Please show me the calculations. I am using 2TTR(R+H) for both shapes but I do not think it is right and then I am not sure how to do the base of the cone.
:
First just find the surface area of the cone
The formula for that: SA = {{{pi*r^2}}} + {{{pi*r*l}}}
:
In your problem r = 3.75 (half the diameter),
:
l is the slanted distance of the cone, 
that will be the hypotenuse of a triangle formed by r and h
l = {{{sqrt(3.75^2 + 22^2)}}}
l = 22.3173 inches
;
SA = {{{pi*3.75^2}}} + {{{pi*3.75*22.3173}}}
SA = 44.1786 + 262.9195
SA = 307.0981 sq inches
:
Add the trunk: {{{pi*d * h}}}
Trunk = {{{pi*3*5}}}
Trunk = 47.1239
:
Total; 307.0981 + 47.1239 = 354.222 sq/in (this includes the circular surface area of the bottom of the trunk)