the ? says "a cone has the surface area of 160 sq. in. If the dimensions are reduced by 1/2,what is the surface area of the new cone?" i just cant seem to find the formula for the surface area of the cone.

3 answers

Check this site.

http://math.about.com/od/formulas/ss/surfaceareavol_2.htm
Surface area cone:

TOP: 1/2 (circumfirance of bottom x height)
= 1/2 (PI*radius x height)
So if you ignore the bottom of the cone, then reducing the dimensions by 1/2...
thanks for helping me