document.write( "Question 311486: The average (arithmetic mean) of 80, 83, 89, and x is the same as the average of 80, 83, and 86. What is the average of 82 and x?\r
\n" ); document.write( "\n" ); document.write( "(A)80 (B) 81 (C) 82 (D) 83 (E) 84
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Algebra.Com's Answer #222849 by ankor@dixie-net.com(22740)\"\" \"About 
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The average (arithmetic mean) of 80, 83, 89, and x is the same as the average of 80, 83, and 86.
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\n" ); document.write( "\"%2880%2B83%2B89%2Bx%29%2F4\" = \"%2880%2B83%2B86%29%2F3\"
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\n" ); document.write( "\"%28252%2Bx%29%2F4\" = \"%28249%29%2F3\"
\n" ); document.write( "Cross multiply
\n" ); document.write( "3(252+x) = 4(249)
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\n" ); document.write( "756 + 3x = 996
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\n" ); document.write( "3x = 996 - 756
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\n" ); document.write( "3x = 240
\n" ); document.write( "x = \"240%2F3\"
\n" ); document.write( "x = 80
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\n" ); document.write( "What is the average of 82 and x?
\n" ); document.write( "\"%2882%2B80%29%2F2\" = 81
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