Answer:
20
Step-by-step explanation:
Standard deviation of the mean is expressed as:
SM = s/√n
s is the standard deviation of all invoices
n is the sample size of the invoiced
Given
s = $200
n = 100
Required
Standard deviation of the mean
Substitute the given parameters into the given equation
SM = 200/√100
SM = 200/10
SM = 20
Hence the standard deviation of xbar is 20
