document.write( "Question 752832: If mean of 100 numbers is 45. The mean that 99 numbers is 44 . What is the first number ? \n" ); document.write( "
Algebra.Com's Answer #458071 by Okeke_Christian(26)\"\" \"About 
You can put this solution on YOUR website!
Formula for Mean (Average) = Sum of all numbers / Total number of numbers\r
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\n" ); document.write( "Mean of 100 numbers = Sum of all hundred numbers / 100\r
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\n" ); document.write( "We don't know the sum of all hundred numbers, so we call it x.\r
\n" ); document.write( "\n" ); document.write( "From the question, mean of 100 numbers is 45. Therefore:\r
\n" ); document.write( "\n" ); document.write( "\"45=%28x%2F100%29\"
\n" ); document.write( "Cross Multiply:
\n" ); document.write( "\"4500=x\"
\n" ); document.write( "Therefore, the sum of those hundred numbers is 4,500.\r
\n" ); document.write( "\n" ); document.write( "Now,
\n" ); document.write( "Mean of 99 numbers = Sum of all ninety-nine numbers / 99\r
\n" ); document.write( "\n" ); document.write( "We don't know the sum of all ninety-nine numbers, so we call it y.\r
\n" ); document.write( "\n" ); document.write( "Mean of 99 numbers is equal to 44 so,\r
\n" ); document.write( "\n" ); document.write( "\"44=%28y%2F99%29\"
\n" ); document.write( "Cross Multiply:
\n" ); document.write( "\"4356=y\"
\n" ); document.write( "Therefore, the sum of the remaining ninety-nine numbers is 4356.
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\n" ); document.write( "Do you rememeber that when we had 100 numbers, the sum was 4,500?
\n" ); document.write( "When we removed one number, the sum became 4,356. So, what was that number we removed?\r
\n" ); document.write( "\n" ); document.write( "\"4500-4356=144\"
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\n" ); document.write( "144 is the first number!
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