SOLUTION: Jessica is 24 years old. She is twice as old as Jane was when Jessica was as old as Jane is now. How old is Jane?

Question 286180: Jessica is 24 years old. She is twice as old as Jane was when Jessica was as old as Jane is now.
How old is Jane?
Answer by Edwin McCravy(20056) (Show Source): You can put this solution on YOUR website!


Let x = Jane's age now.

Jane was 12 when Jessica was Jane's present age, x.

Let y = the number of years ago it's been since Jane was 12
and Jessica was x. 

Jessica's age y years ago = Jane's age now.

                   24 - y = x

   Jane's age y years ago = 12

                    x - y = 12

So we have this system:



Can you solve that system?  If not post again asking how,

x=18, y=6

So Jane is 18 years old now.  

Checking:  y=6 years ago, Jane was 12, and Jessica was 18. Today
Jessica is twice 12, Jane's age then.

Edwin

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