• Jun 15th 2005, 03:14 AM
Nicv
11 years ago Helen was four times as old as Ed. In one year Helen will be two times Ed's age. How old are they now?

I also need to see the formula so I can try to learn the process. Thanks
so much!
• Jun 15th 2005, 03:54 AM
Delta
17 and 35?
• Jun 15th 2005, 04:00 AM
Nicv
I also need to know how to do it! Thanks
• Jun 15th 2005, 04:40 AM
Delta
I didn't use a formula as such, I just woked it out by trial and error using what is said in the question. I didn't start at Ed being one or two because their ages would be too close together.

I tried:
Ed Helen
3 12
add 11 to both to get:
14 23
add 1 to both to get:
15 24

Helen is not two times Ed's age yet, so carry on until she is.

Ed Helen
6 24
add 11 to both to get:
17 35
add 1 to both to get:
18 36

So, in a years time, Helen will be twice Ed's age, but they want their ages now, so it's 17 and 35.

I'm not very good at the explanation part, so maybe someone else will be able to help better.
• Jun 15th 2005, 09:12 AM
Math Help
Two equations two unknowns
Quote:

Originally Posted by Nicv
11 years ago Helen was four times as old as Ed. In one year Helen will be two times Ed's age. How old are they now?

I also need to see the formula so I can try to learn the process. Thanks
so much!

$H-11=4(E-11)$
$H+1=2(E+1)$

Then you have two equations and two unknowns.
• Jun 17th 2005, 07:23 AM
Nicv
Just don't know where to begin with this one!
• Jun 17th 2005, 08:58 AM
Math Help
Begining the problem
To begin:

You must extract relevant information from the problem:

1. 11 years ago Helen was four times as old as Ed
2. In one year Helen will be two times Ed's age

Then convert those two sentances into equations as I did above.

Once you have two equations and two unknowns it is a matter of substitution which I can help you along with if you need it.

Try to make sense of the equations I posted above and hopefully you will have your "aha!" moment.
• Jun 17th 2005, 11:18 AM
Nicv
I think the problem for me is that I can figure it out when I am only looking for one variable. Would it work for me if I used Helen as H and the brother as H4?

H-11=4(H-11)

H+1=2(H+1)

This class is a seven week elementary algebra class and I have never taken this stuff before.