<PRE><B>Question 1196293</B>
&lt;br&gt;
You have 4 responses already; however, they are all very similar, so I will show a different method that is sometimes convenient to use in a problem involving the average of several numbers that are relatively close together.&lt;br&gt;
Comparing each quiz score to the desired average, we have the following:&lt;pre&gt;
   87:  +2
   89:  +4
   88:  +3
   78:  -7
   -------
total:  +2&lt;br&gt;&lt;/pre&gt;
All together, the 4 quiz scores are +2 compared to the desired average.  Since the test counts as much as 2 quizzes, the score on the test, to balance the scores on the quizzes, must be -1 compared to the desired average.  So the score on the test to make an average of 85 is 85-1 = 84.&lt;br&gt;
ANSWER: 84&lt;br&gt;
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