Statistics
posted by Kathy .
A random sample of 150 towns in a western state had a mean annual precipitation of 2.86 inches. Assume that the population standard deviation is known to be 0.78 inches. Compute the 95% confidence interval for μ.

Statistics 
PsyDAG
95% = mean ± 1.96 SEm
SEm = SD/√n
I'll let you do the calculations.
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