document.write( "Question 141660: Your math teacher says you have an 86.5% test average after 8 tests. You will be taking 4 more tests and hope to raise your overall test average to 90%. What do you need to average on the next 4 tests in order to reach that goal? \n" ); document.write( "
Algebra.Com's Answer #103214 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
The average of your first 8 scores, A, is the sum of the 8 scores divided by 8.
\n" ); document.write( "The average of your 12 scores,B, is the sum of the 12 scores divided by 12.
\n" ); document.write( "A=SUM8/8
\n" ); document.write( "SUM8=8A
\n" ); document.write( "SUM8=8(0.865)
\n" ); document.write( "SUM8=6.92
\n" ); document.write( "B=SUM12/12
\n" ); document.write( "SUM12=12B
\n" ); document.write( "SUM12=12(.90)
\n" ); document.write( "SUM12=10.8
\n" ); document.write( "SUM12=SUM8+NINE+TEN+ELEVEN+TWELVE
\n" ); document.write( "where NINE, TEN, ELEVEN, and TWELVE are test scores 9,10,11, and 12.
\n" ); document.write( "SUM12=SUM8+NINE+TEN+ELEVEN+TWELVE
\n" ); document.write( "10.8=6.92+NINE+TEN+ELEVEN+TWELVE
\n" ); document.write( "NINE+TEN+ELEVEN+TWELVE=3.88
\n" ); document.write( "(NINE+TEN+ELEVEN+TWELVE)/4=3.88/4
\n" ); document.write( "(NINE+TEN+ELEVEN+TWELVE)/4=0.97\r
\n" ); document.write( "\n" ); document.write( "You need to average a 97% on the next four tests to get 90% average.
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