document.write( "Question 328054: In a science test a class of 30 students had an average of 80. The 20 girls had an average of 85. Whats the average of the 10 remaining boys? \n" ); document.write( "

Algebra.Com's Answer #234949 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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In a science test a class of 30 students had an average of 80.
\n" ); document.write( " The 20 girls had an average of 85.
\n" ); document.write( " What's the average of the 10 remaining boys?
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\n" ); document.write( "Let x = av of the 10 boys
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\n" ); document.write( " $\"%2820%2885%29%2B10x%29%2F30\"$ = 80
\n" ); document.write( "multiply both sides by 30, results
\n" ); document.write( "20(85) + 10x = 30(80)
\n" ); document.write( "1700 + 10x = 2400
\n" ); document.write( "10x = 2400 - 1700
\n" ); document.write( "10x = 700
\n" ); document.write( "x = $\"700%2F10\"$
\n" ); document.write( "x = 70 is the av of the 10 boys \n" ); document.write( "

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