SOLUTION: I am trying to find the volume of a composite figure. The figure Is a cylinder that is 3 inches in height and 3 inches in length. Attached to one end of the cylinder is a cone whic

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Question 189329This question is from textbook Pre-Algebra
: I am trying to find the volume of a composite figure. The figure Is a cylinder that is 3 inches in height and 3 inches in length. Attached to one end of the cylinder is a cone which is 2 inches in length. The book wants me to find the volume of the composite figure. The following is what I've tried.
V= pi(r)to the power of 2 x H.
V= pi (3)to the power of 2 x 3 + 1/2 x 4/3 pi (2) to the power of 3.
V= pi (9)(3) + 2/3 pi (8)
V= 27 pi + 16.76 pi = 43.76pi.
So the answer would of been 43.76 pi. My teacher tells me this is wrong. So, I guess I need a new method for working this problem, and information to help me understand this topic better. Can you help??
Thanks
~Ave
This question is from textbook Pre-Algebra

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
I am trying to find the volume of a composite figure. The figure Is a cylinder that is 3 inches in height and 3 inches in length. Attached to one end of the cylinder is a cone which is 2 inches in length. The book wants me to find the volume of the composite figure. The following is what I've tried.
V= pi(r)to the power of 2 x H.
V= pi (3)to the power of 2 x 3 + 1/2 x 4/3 pi (2) to the power of 3.
V= pi (9)(3) + 2/3 pi (8)
V= 27 pi + 16.76 pi = 43.76pi.
:
Lets see what I get when I attack this problem
V = cylinder vol + Cone vol
V = pi%2Ar%5E2%2Ah + %281%2F3%29%2Api%2Ar%5E2%2Ah
I have to assume that one of those 3" measurements is the diameter, therefore
r = 1.5 inches
V = pi%2A1.5%5E2%2A3 + %281%2F3%29%2Api%2A1.5%5E2%2A2
V = 21.20575 + 4.7124
V = 25.9 cu/in
:
It looks like you got the vol of a sphere instead of the vol of a cone
:
Did this make sense to you?