Question 396799
<font face="Times New Roman" size="+2">


If you want the average of 4 numbers, you add the numbers and divide by 4.  So if you have the average of 4 numbers, the sum of those numbers must be the average multiplied by 4.


Add the three scores already received.  Multiply 85 by 4.  Subtract the sum of the first three scores.  The result will be the score required to achieve the stated average.  You might want to compare the score required to the maximum score possible on the last test, if you know it.  After all, it is possible that the stated average cannot be achieved.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
<div style="text-align:center"><a href="http://outcampaign.org/" target="_blank"><img src="http://cdn.cloudfiles.mosso.com/c116811/scarlet_A.png" border="0" alt="The Out Campaign: Scarlet Letter of Atheism" width="143" height="122" /></a></div>
</font>