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