<PRE><B>Question 1203735</B>
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The given fact that the sum of their ages is not needed; the problem can be solved with the other information.&lt;br&gt;
Jess is 15.
Jess is younger than Sam and older than Mindy.
Mindy is the youngest, by 6 years, so Mindy is 15-6 = 9.
Sam is twice as old as Mindy, so he is 9*2 = 18.&lt;br&gt;
Yes, the sum of their ages is 15+9+18 = 42 -- but we didn&#39;t need that information to solve the problem.&lt;br&gt;
ANSWER: Mindy is 9, Sam is 18&lt;br&gt;
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Note the solution from tutor @josgarithmetic uses an equation that says Mindy is 6 years younger than Sam, which is not correct, leading of course to a wrong solution.  The tutor should have realized the solution was wrong, since the sum of the ages he ended up with is not 42.&lt;br&gt;
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