An auto insurance company has 15,000 policyholders with comprehensive automobile coverage. In the past year, 11,425 filed no claims, 3,100 filed one claim, 385 filed two claims, and 90 filed 3 claims.
(a) Calculate the mean and for the number of claims filed by a policyholder
(b) Calculate the standard deviation for the number of claims filed by a policyholder.
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