document.write( "Question 307089: after taking 7 quizzes, your average is 78 out of 100. what must your average score be on the next five quizzes to increase your average to 83?
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Algebra.Com's Answer #219825 by ankor@dixie-net.com(22740)\"\" \"About 
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after taking 7 quizzes, your average is 78 out of 100.
\n" ); document.write( " what must your average score be on the next five quizzes to increase your average to 83?
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\n" ); document.write( "Let x = av score on the next 5 quizzes
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\n" ); document.write( "We want the average for 7 + 5 = 12 quizzes
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\n" ); document.write( "\"%287%2878%29+%2B+5x%29%2F12\" = 83
\n" ); document.write( "\"%28546+%2B+5x%29%2F12\" = 83
\n" ); document.write( "Multiply both sides by 12
\n" ); document.write( "546 + 5x = 12(83)
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\n" ); document.write( "546 + 5x = 996
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\n" ); document.write( "5x = 996 - 546
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\n" ); document.write( "5x = 450
\n" ); document.write( "x = \"450%2F4\"
\n" ); document.write( "x = 90 av required on the next 5 quizzes \n" ); document.write( "
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