document.write( "Question 241050: Andrea has an average of 87% on her first 5 tests. She has one test left to take. What is the lowest score Andrea can get and still have an average of at least 80% on her test?
\n" ); document.write( "A) 45 B) 73 C) 80 D) 43 \n" ); document.write( "

Algebra.Com's Answer #176562 by checkley77(12844) $\"\"$ $\"About$

You can put this solution on YOUR website!
(87*5+x)/6>=80
\n" ); document.write( "(435+x)/6>=80
\n" ); document.write( "435+x>=6*80
\n" ); document.write( "435+x>=480
\n" ); document.write( "x>=480-435
\n" ); document.write( "x>=45 is the minimum test score to maintain an 80 average.
\n" ); document.write( "Proof:
\n" ); document.write( "(87*5+45)/6>=80
\n" ); document.write( "(435+45)/6>=80
\n" ); document.write( "480/6>=80
\n" ); document.write( "80>=80
\n" ); document.write( " \n" ); document.write( "

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