Answer:
Step-by-step explanation:
Sample mean x bar = 98.9
Std dev s = 0.62
Sample size n = 106
Std error =
Since population std deviation not known we can use t critical value.
t critical for 99% with df = 105 is 1.98
Margin of error = ±1.98(0.0602) =±0.1192
Confidence interval for sample mean = (98.9±0.1192)
=(98.781, 99.019)
2) Sample mean confidence interval suggests that sample mean is different from the population since 98.6 is not contained in the confidence interval.
3) Population interval confidence mean would be
98.6±0.1192
=(98.4808, 98.7192)