The population mean and standard deviation are given below. Find the required probability and determine whether the given sample mean would be considered unusual.

For a sample of n= 61, find the probability of a sample mean being less than 20.5 if u=21 and sigma=1.34

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For a sample of n= 61, the probability of a sample mean being less than 20.5 if u= 21 and sigma=1.34 is____