You can use either. I prefer to use ONLY 1. 

In this case, I'd let Jean's age be J

Then, 3 years ago, Jean was J - 3

Therefore, Tom's age then, was: 2(J - 3), or 2J - 6, which makes Tom's current age: 2J - 6 + 3, or 2J - 3

We then get: J + 2 + 2J - 3 + 2 = 28

Solve for J, Jean's current age.

Then calculate: 2J - 3 for Tom's current age. 

Answer by ikleyn(52802)   (Show Source): You can put this solution on YOUR website!
 .

There is a bunch of lessons on age word problems 



    - Age problems and their solutions



    - A fresh formulation of a traditional age problem



    - Really intricate age word problem



    - Selected age word problems from the archive



in this site.





Read them and become an expert in solving age problems.





Also, you have this free of charge online textbook in ALGEBRA-I in this site



    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.





The referred lessons are the part of this online textbook under the topic "Age word problems".





---------------

When you read these lessons, you will get understanding that it is not the question to argue: one or two variables.





You can solve these problems using one variable (in the most simplest cases).





You can also solve them in two variables, and sometimes it works better in complex cases.





What you REALLY NEED is to learn both techniques and apply which suits better for the concrete problem.







So,     h a p p y   l e a r n i n g  ! !







 

RELATED QUESTIONS

three years ago Tom was twice as old as Jean, and in two years the sum of their ages will  (answered by ankor@dixie-net.com)

Three times the sum of Jim’s and Tom’s ages is equal to twelve times the difference of... (answered by josgarithmetic)

For the problem I have to solve it says I have to write a system of equations involving... (answered by ankor@dixie-net.com,jrfrunner)

THREE TIMES THE SUM OF JIMS AND TOMS AGES IS EQUAL TO TWELVE TIMES THE DIFFERENCE OF... (answered by JBarnum)

Three years ago, Juma was three times as old as Ali. In two years time, the sum of their... (answered by mananth,richwmiller)

Two years ago John was three times as old as Frank. Five years from now John will be... (answered by Edwin McCravy)

two years ago john was twice as old as jude. in 4 years the sum of their age will be 30.... (answered by lwsshak3)

in 4 years, jean will be twice as old as she was 6 years ago. how old is jean?

 (answered by Cromlix)

6.  Three times the sum of Jim’s and Tom’s ages is equal to nine times the difference of... (answered by Edwin McCravy)