document.write( "Question 538086: Josh has scored 65, 71, and 91 on his last three tests. what score must he get on his next exam to have an average (mean) of 80? \n" ); document.write( "
Algebra.Com's Answer #353103 by Gurukool(2)\"\" \"About 
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Assume he has to score X in the next exam.\r
\n" ); document.write( "\n" ); document.write( "Then (65 + 71 + 91 + X)/4 = 80\r
\n" ); document.write( "\n" ); document.write( "=> X = 80*4 - (65 + 71 + 91)\r
\n" ); document.write( "\n" ); document.write( "=> X = 93\r
\n" ); document.write( "\n" ); document.write( "So Josh has to score 93 in the next exam to have an average of 80.
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