<PRE><B>Question 1186453</B>
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The solution from the other tutor is fine; I would set it up differently.&lt;br&gt;
Given that Mario was 3 times as old as Luigi 4 years ago, I would do this:&lt;br&gt;
Let x = Luigi&#39;s age 4 years ago
Then 3x = Mario&#39;s age 4 years ago&lt;br&gt;
Given that the sum of their ages now is 80, do some simple mental arithmetic to determine that 4 years ago the sum of their ages was 72.  Then&lt;br&gt;
3x+x=72
4x=72
x=18&lt;br&gt;
Their ages 4 years ago were
Luigi = x = 18
Mario = 3x = 54&lt;br&gt;
ANSWER: Mario&#39;s age now is 54+4 = 58&lt;br&gt;
Note setting the problem up that way leads to algebra that is simpler than in the solution from the other tutor.&lt;br&gt;
And if formal algebra is not required, and/or if the speed of reaching a solution is important -- as in a timed math competition -- solving the problem by this method can be done mentally in far less time than with the formal method shown by the other tutor.&lt;br&gt;
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