Answer:
92% Confidence Interval = [8.515, 8.605]
Step-by-step explanation:
The number of samples given is 15,this less than 30, hence, we use the t score confidence Interval
= Mean ± t score × Standard deviation/√n
Mean = 8.56 ounces
Standard deviation = 0.09 ounces
n = 15
We find the degrees of freedom = n - 1
= 15 - 1 = 14
Using the T score table
T score for 92% confidence interval with degrees of freedom 14
= 1.8875
Hence:
Confidence Interval =
= 8.56 ± 1.8875 × 0.09/√15
= 8.56 ± 0.0454010035
Confidence Interval
8.56 - 0.0454010035
= 8.5145989965
≈ 8.515
8.56 + 0.0454010035
= 8.6054010035
≈ 8.605
92% Confidence Interval = [8.515, 8.605]
