SOLUTION: In 8 tests, Grace achieved an average of 72%. After her ninth test, she had an average of 74%. 
What percentage did she get for her ninth test? 
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Question 852652:  In 8 tests, Grace achieved an average of 72%. After her ninth test, she had an average of 74%. 
What percentage did she get for her ninth test?  
Answer by JulietG(1812)   (Show Source): You can put this solution on YOUR website!
 In 8 tests, Grace has an average of 72.  72*8=576 out of a possible 800.
After 9 tests, there are a possible 900.  .74*900=666.
If she know has 666 points, and before this last test had 576 points, what was her score on the last exam?  666-576=90. 
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