<PRE><B>Question 1168156</B>
&lt;br&gt;
An average of 90 on 5 tests means a total of 450 points:&lt;br&gt;
{{{92+86+79+96+x = 450}}}&lt;br&gt;
Solve for x using basic algebra.&lt;br&gt;
In cases like this involving the average of a set of numbers that are all close together, there is another quick way to solve the problem -- by balancing the &quot;overs&quot; and &quot;unders&quot;.&lt;br&gt;
Comparing each score to the desired average....&lt;br&gt;&lt;pre&gt;
   92:  +2
   86:  -4
   79: -11
   96:  +6
   -------
 total: -7&lt;/pre&gt;&lt;br&gt;
Through the first four tests, the student is 7 points under the total they need, so the 5th test must be 7 points over the desired average.&lt;br&gt;
ANSWER: 90+7 = 97&lt;br&gt;
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