I know what it is. I don't understand a particular problem asking me to form a two-sided confidence interval. I am given the mean age of participants in a study, which is 31.5 years, and standard deviation, which is 10.2. Based on this, I found one standard error to be 1.33. However, I understand, from my book, that a Z score would be next, but I don't know how to find μ.

Jun 8th, 2015

I guess I don't even understand what it's asking. Is it asking for the interval in which the researching is 95% confident the population mean will fall under?