Question

The following sample data is taken from the normal population: 10, 8, 12, 15, 13, 11, 6, 5.
a. What is the estimator of the average population
b. What is the estimator of the population standard deviation
c. At the 95% confidence level, what is the error margin of the population mean estimator
d. Determine 95% confidence intervals for the population mean

Answer 1

x : sample data

sr.no.	X	X-X̅	(X-X̅)2
1	10	0	0
2	8	-2	4
3	12	2	4
4	15	5	25
5	13	3	9
6	11	1	1
7	6	-4	16
8	5	-5	25
Total=	80		84
mean=X̅	Total/8
X̅	10