Question 411983
<font face="Times New Roman" size="+2">


To take the average, you add up all of the numbers and divide by the number of numbers.  Given that, if you multiply the average by the number of numbers, you must have the sum of all of the numbers.  So, if you want to have an average of 80 over 9 tests, you multiply 9 times 80 and that will give you the sum you must achieve.  Add up the scores that you already have and subtract from 9 times 80 to get the score you have to achieve to make an 80 average.


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>