Solution:
We are given
Standard deviation = S = 6.9
Sample size = n = 100
Standard error of the mean = s.e.(x̄) = S/sqrt(n) = 6.9/sqrt(100) = 6.9/10 = 0.69
Answer: 0.69
A randomly selected sample of n = 100 individuals over 65 years old takes a test...
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