posted by Steph .
Suppose x has a mound-shaped distribution with sigma = 9 . A random sample of size 36 has sample mean 20. Is it appropriate to use a normal distribution to compute a confidence interval for the population mean m? Explain. Find a 95% confidence interval for m. Explain the meaning of the confidence interval you computed.
95% = mean ± 1.96 SEm
SEm = SD/√n
I'll let you explain what it means.