<PRE><B>Question 1167887</B>
&lt;br&gt;
By formal algebra....&lt;br&gt;
x = Ben&#39;s age now
3x = Ari&#39;s age now
x+6 = Ben&#39;s age 6 years from now
3x+6 = Ari&#39;s age 6 years from now&lt;br&gt;
The sum of their ages 6 years from now will be 84:
{{{(x+6)+(3x+6) = 84}}}&lt;br&gt;
Solve using basic algebra; then remember the answer to the question is Ben&#39;s age 6 years from now, which is x+6 -- not just x.&lt;br&gt;
Informally, using logical reasoning and simple arithmetic (good brain exercise!)....&lt;br&gt;
The sum of their ages 6 years from now will be 84, so the sum of their ages now (subtract 6 years for each of them) is 72.&lt;br&gt;
Since Ari is now 3 times as old as Ben, simple mental arithmetic tells us Ben is now 18 and Ari is 54.&lt;br&gt;
So Ben&#39;s age 6 years from now will be 18+6=24.&lt;br&gt;
If you completed solving the problem using the formal algebra method suggested above, you will see that the formal algebra used exactly the same calculations as the informal solution.&lt;br&gt;
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