document.write( "Question 510906: Flora had an average of 83% on her first 7 exams. What would she have to get on her eighth exam to obtain an average of 90%? \n" ); document.write( "

Algebra.Com's Answer #341922 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let's find the sum of her first seven scores, we'll call this y:
\n" ); document.write( " $\"y%2F7+=+83\"$ Multiply both sides by 7.
\n" ); document.write( " $\"y+=+581\"$ Now you want the average of eight test scores to be 90. Lets call the score of the eighth test x, so...
\n" ); document.write( " $\"%28581%2Bx%29%2F8+=+90\"$ Multiply both sides by 8.
\n" ); document.write( " $\"581%2Bx+=+720\"$ Subtract 581 from both sides.
\n" ); document.write( " $\"x+=+139\"$
\n" ); document.write( "Flora will need to score 139% on test eight. Not possible! \n" ); document.write( "

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