Assigning Variables for Age
Date: 02/21/2003 at 23:46:45 From: G. G. Subject: How to calculate age of individuals current and present John is 32. He is twice as old as Jim was when John was as old as Jim is now. How old is Jim? I don't understand how to assign the variables that will give me the answer to this problem.
Date: 02/22/2003 at 20:55:30 From: Doctor Peterson Subject: Re: How to calculate age of individuals current and present Hi, G. G. My technique is to define a variable each time a new "when" is mentioned. We'll start with x = Jim's age now So we have He is twice as old as Jim was when 32 = 2 * (x - a) where this "when" is "a" years ago. Continuing, John was as old as Jim is now. (32 - a) = x In other words, I pull the subordinate clause out into its own sentence like this: He is twice as old as Jim was a years ago. a years ago, John was as old as Jim is now. See if you can take this and solve for x. If you need more help, please write back and show me how far you got. - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
Search the Dr. Math Library:
Ask Dr. MathTM
© 1994-2013 The Math Forum