SOLUTION: I have a couple of problems that I am trying to help my daughter to understand but I admit it's been years and I can't remember how to do them so I am going to submit them one at a

Question 140540: I have a couple of problems that I am trying to help my daughter to understand but I admit it's been years and I can't remember how to do them so I am going to submit them one at a time. I hope someone can help me help her. Here's the question: A cylinder has a volume of 85.6 cubic meters. If the radius is tripled and the height is doubled, what is the volume of the new cylinder? Thanks for your help!! Jennifer
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
A cylinder has a volume of 85.6 cubic meters. If the radius is tripled and the height is doubled, what is the volume of the new cylinder?
:
The volume of a cylinder V = pi*r^2*h
You may be able to just look at this and see that it would be 18 times as much
Anyway here is method:
:
85.6 = pi*r^2*h
;
Let x = new cylinder volume
If you tripled the radius and doubled the height you could write it like this:
x = pi* (3r)^2 * 2h
x = pi * 9r^2 * 2h
:
A proportion equation:
=
Cancel our like terms and you have:
= which is: =
Cross multiply:
1x = 18 * 85.6
x = 1540.8

RELATED QUESTIONS
I have a couple of problems that I am trying to help my daughter to understand but I... (answered by scott8148)

I have a couple of problems that I am trying to help my daughter to understand but I... (answered by ankor@dixie-net.com)

I am trying to help my grandson get caught up in online school Algebra but I don't know... (answered by macston)

Hi I am having really bad trouble with this problem and i have used all the posible... (answered by stanbon,funmath)

Is anyone familar with Flow Proofs in geometry? I am trying to assit my daughter in H.S. (answered by stanbon)

I am trying to help my daughter with her homework and it has been a while since... (answered by Alwayscheerful)

I don't have any idea how to do these word problems. I've been trying but I just don't... (answered by KnightOwlTutor)

I am trying to help my daughter with homework and apparently it has been too long since I (answered by mananth)

I'm trying to help my niece with an algebra problem that has both of us stumped...... (answered by shree840,mananth,Alan3354)