# Thread: Surface Area and Volume with Cones

1. ## Surface Area and Volume with Cones

The length of each dimension of a cone is increased by 20%.
a. What is the percent increase in the surface area of the resulting figure?
b. What is the percent increase in the volume of the resulting figure?

2. Originally Posted by monkeymath
The length of each dimension of a cone is increased by 20%.
a. What is the percent increase in the surface area of the resulting figure?
b. What is the percent increase in the volume of the resulting figure?
the fact that the solid is a cone is immaterial ...

if you increase each linear dimension by 20%, then the area will be increased by $\frac{(1.2)^2}{(1)^2} = 44$%

same idea for the volume, except that the linear dimensions are efectively cubed ... $\frac{(1.2)^3}{(1)^2} = 72.8$%

check it out using some actual values for any solid ... try something simple like a cube.

3. I'm sorry but I don't follow you at all... I don't know where those numbers came from or what they mean... Please explain. Thanks!

4. Originally Posted by monkeymath
I'm sorry but I don't follow you at all... I don't know where those numbers came from or what they mean... Please explain. Thanks!
Hmm... They were supposed to have covered this topic before you were assigned homework on it...

To understand the worked solution that was provided, you'll first need to study the topic. So please read through at least three online lessons.

Once you have learned the basic terms and techniques, please review the solution you were given. If you have questions, you will then be able to reply with a clear statement of where you are getting stuck.

Thank you!