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Subject: "Solution needed for a Logic Problem"     Previous Topic | Next Topic
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Conferences The CTK Exchange College math Topic #563
Reading Topic #563
Teresa
guest
Mar-18-06, 08:23 PM (EST)
 
"Solution needed for a Logic Problem"
 
   Would you be able to tell me if you have the solution to this Logic Problem.

"Billy is twice as old as Sally was when Billy was as old as Sally is now. And the sum of their ages is 28. How old are they now?"

This would really help me
Thanks
Teresa


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alexb
Charter Member
1807 posts
Mar-23-06, 06:56 AM (EST)
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1. "RE: Solution needed for a Logic Problem"
In response to message #0
 
   Please have a look at

https://www.cut-the-knot.org/Outline/WordProblems/BillIsTwiceAsOldAsSally.shtml


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iliaden
Member since Aug-14-05
Mar-26-06, 07:38 PM (EST)
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2. "RE: Solution needed for a Logic Problem"
In response to message #0
 
   Take Billy's age as B and Sally's age as S. then we have:

B+S=28
B=2( S-(B-S) )
By deduction, we have that Billy is older than Sally.



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