document.write( "Question 748630: The mean of five numbers is 12 . If the first four numbers are 7,9,10 and 13 , find the fifth number . \n" ); document.write( "
Algebra.Com's Answer #455551 by Cromlix(4381)\"\" \"About 
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If the mean of 5 numbers is 12
\n" ); document.write( "then the full total must = 5 x 12 = 60
\n" ); document.write( "Adding up the given numbers 7,9,10 and
\n" ); document.write( "13 totals 39.
\n" ); document.write( "Therefore the missing number must be
\n" ); document.write( "60 - 39 = 21.
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