In the claims department of an insurance office various quantities are computed at the

end of each day's business. On Monday, 20 claims are received for a particular class of

policy. The mean claim amount is calculated to be K4,500 and the standard deviation

to be K2,540. On Tuesday, the claims are reviewed and one claim which was incorrectly

recorded as K13,000 is now corrected to K3,000.

Determine the mean and standard deviation of the corrected set of claims.