document.write( "Question 1201185: In the claims department of an insurance office various quantities are
\n" ); document.write( "computed at the end of each day’s business. On Monday, 20 claims are
\n" ); document.write( "received for a particular class of policy. The mean claim amount is calculated
\n" ); document.write( "to be K4,500 and the standard deviation to be K2,540. On Tuesday, the
\n" ); document.write( "claims are reviewed and one claim which was incorrectly recorded as K13,000
\n" ); document.write( "is now corrected to K3,000. Determine the mean and standard deviation of
\n" ); document.write( "the corrected set of claims \n" ); document.write( "
Algebra.Com's Answer #835485 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
i think it's going to work like this.
\n" ); document.write( "the mean of 4500 * 20 = sum of 90,000
\n" ); document.write( "subtract 13000 from that and add 3000 to that leaves a sum of 80000.
\n" ); document.write( "divide that by 20 to get a new mean of 4000.
\n" ); document.write( "square the original standard deviation of 2540 to get a variance of 64516001.
\n" ); document.write( "mutliply that by 20 to get a sum of squares of 129032000.
\n" ); document.write( "13000 - 4500 = original deviation of 8500.
\n" ); document.write( "square that to get a squared deviation of 72250000.
\n" ); document.write( "subtract that from the original sum of squares to get a sum of squares of 56782000.
\n" ); document.write( "3000 - 4000 = revised deviation of -1000.
\n" ); document.write( "square that to get a squared deviation of 1000000.
\n" ); document.write( "add that to the sum of squares to get a revised sum of squares of 57782000.
\n" ); document.write( "divide that by 20 to get a new variance of 2889100.
\n" ); document.write( "take the square root of that to get a new standard deviation of 1699.735274.
\n" ); document.write( "if i did this correctly, your solution should be:
\n" ); document.write( "mean of corrected claims is 4000.
\n" ); document.write( "standard deviation of corrected claims is 1699.735274.
\n" ); document.write( "here's a reference on how to calculate standard deviation.
\n" ); document.write( "https://www.mathsisfun.com/data/standard-deviation-formulas.html\r
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