Is My Solution For This Cone's Surface Area & Volume Correct

[Serabi]

Just the cone in this photo: http://s442.photobucket.com/albums/qq142/French_Bordeaux/?action=view&current=conesphere.jpg

*note* Answers were meant to be left in terms of pi*

I got 320pi for the Volume and 200pi for the surface area. but my teacher said it was wrong.

What are the right answers?
Can you show me in steps how to get the answers?

 

[wjm11]

Cone volume, V = pi(r^22)h/3 = pi(8^2)(15)/3 = 320pi ft^3

Surface area of side of cone, SA = pi(r)(s) = pi(8)(17) = 136pi
Base: A = pi(r^2) = pi(64)
Total SA = (136 + 64)pi = 200pi ft^2

 

[Serabi]

So, she was wrong about me being wrong?

 

[Deleted member 4993]

So, she was wrong about me being wrong?

May be not.

It depends on how you got to the answer - which we don't know.

Suppose I asked you

how much is 2[sup:cw4iton7]2[/sup:cw4iton7]?

and you said it is 2 + 2 = 4

You would be wrong - even if you got the answer right.

 

[wjm11]

Did you remember to put units on your answers? I notice that you did not put units on your answers here. Units are required for correct answers in most cases.

 

[geo_lover]

I got the same answers and like wjm11 said, it could be that you left your units or something...