Answer:
7.79771≤x≤8.20229
Step-by-step explanation:
Given the following
sample size n = 8
standard deviation s = 0.238
Sample mean = 2.275
z-score at 980% = 1.282
Confidence Interval = x ± z×s/√n
Confidence Interval = 8 ± 1.282×0.238/1.5083)
Confidence Interval = 8 ± (1.282×0.15779)
Confidence Interval = 8 ±0.20229
CI = {8-0.20229, 8+0.20229}
CI = {7.79771, 8.20229}
Hence the required confidence interval is 7.79771≤x≤8.20229