SOLUTION: Assuming the population has an approximate normal distribution, if a sample size n=28 has a sample mean x¯=39 with a sample standard deviation s=2, find the margin of error at a

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Question 1206865: Assuming the population has an approximate normal distribution, if a sample size
n=28 has a sample mean x¯=39 with a sample standard deviation s=2, find the margin of error at a 80% confidence level. Round the answer to two decimal places.

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Margin of error =+Z+%2A+%28mu+%2F+sqrt%28n%29%29
Where:
Z is Z-score corresponding to the desired confidence level (for a 80% confidence level, Z1.282)
a sample size n=28+
a sample mean x¯=39 or mu=39
a sample standard deviation s=2

Margin of error = 1.282+%2A+%2839+%2F+sqrt%2828%29%29
Margin of error =+1.282+%2A+%287.37030722367993%29
Margin of error = 9.45