You are a researcher studying the health habits of people living in a large rural area In particular you are interested in the amount of weight gained early in life You want to estimate the population mean of all weight gains for the area s baby girls in their first year To estimate the population mean of all such weight gains you select a random sample of 12 baby girls from this area and you record the weight in kg each gained in their first year Assume the population is approximately normally distributed Based on your sample follow the steps below to construct a 90 confidence interval of the weight gains in the first year for all the area s baby girls If necessary consult a list of formulas 0 Click on Take Sample to see the results for your random sample Sample size Point estimate Enter the values of the sample size the point estimate of the mean the sample standard deviation and the critical value you need for your 90 confidence interval Choose the correct critical value from the table of critical value provided When you are done select Compute Sample standard deviation 0 Compute Number of baby girls BXK 0 000 12 180 Sample mean 5 322 Standard error 4 Margin of error 90 confidence interval Based on your sample enter the lower and upper limits to graph the 90 confidence interval for the population mean of the weight gains in the first year for all the area s baby girls 90 condence interval 5 Critical value e 1 106