SOLUTION: John recently scored a 96 on a 100-point test. This score brought his overall test average up percentage points to 81%. How many tests has John's class taken in total if every tes

Algebra ->  Average -> SOLUTION: John recently scored a 96 on a 100-point test. This score brought his overall test average up percentage points to 81%. How many tests has John's class taken in total if every tes      Log On


   



Question 784597: John recently scored a 96 on a 100-point test. This score brought his overall test average up percentage points to 81%. How many tests has John's class taken in total if every test was 100 points?
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


You didn't provide all of the required information. You wrote "...test average up percentage points..." and left out a number between "up" and "percentage". So let's call that number . Let's call the number of tests taken .

If the final average is 81, then the total points scored on tests is . The total points before the last test must then have been either or , meaning that this is two ways of arriving at the same number. Hence:



Once you figure out what was supposed to have been, substitute it and do the arithmetic. Then solve for

John

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