Question

The yields for the last six batches from a chemical reactor are:
61.84, 61.18, 64.71, 62.83, 62.66, 62.47.
Assuming that these yields form a random sample from a normal population, but sample size is too SMALL to assume s ≈ σ, construct a 99% confidence interval for the true mean yield.

	t-values for tail area α
ν	0.100	0.050	0.025	0.010	0.005
1	3.078	6.314	12.706	31.821	63.657
2	1.886	2.920	4.303	6.965	9.925
3	1.638	2.353	3.182	4.541	5.841
4	1.533	2.132	2.776	3.747	4.604
5	1.476	2.015	2.571	3.365	4.032
6	1.440	1.943	2.447	3.143	3.707
7	1.415	1.895	2.365	2.998	3.499
8	1.397	1.860	2.306	2.896	3.355
9	1.383	1.833	2.262	2.821	3.250
10	1.372	1.812	2.228	2.764	3.169

Your answers can be rounded to three decimal digit accuracy when entered.

Lower limit is =				Upper limit is =

Answer 1