The confidence interval gives you a range of values that's likely to include a population value with a certain confidence level, in this case, 99%.
It also depends of the sample size.
In this problem, the student has to find an interval for widget width.
Then, the interval 10.5<μ<21.1 can be interpreted as:
- With 99% confidence, the mean width of a randomly selected widget will be between 10.5 and 21.1
