document.write( "Question 266578: gine earns score of 65,78,85 and 82 on four tests. what grade must she earn on the next test to have an average of 80 ? \n" ); document.write( "
Algebra.Com's Answer #198940 by mawskittykat(9)\"\" \"About 
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First of all you need to add all 4 grades
\n" ); document.write( "65+78+85+82=310 (you Have)\r
\n" ); document.write( "\n" ); document.write( "If you took 5 tests your total would need to be 400 to receive and 80 average overall. Because 400 divided by 5 equals 80\r
\n" ); document.write( "\n" ); document.write( "Now you would subtract the 400 you need minus 310 you have.
\n" ); document.write( "400-310 = 90.\r
\n" ); document.write( "\n" ); document.write( "You would need to score 90 on your next test
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