Answer:
Correct option: (a)
Step-by-step explanation:
A confidence interval is an interval estimate of the parameter value.
A (1 - <em>α</em>)% confidence interval implies that the confidence interval has a (1 - <em>α</em>)% probability of consisting the true parameter value.
OR
If 100 such confidence intervals are made then (1 - <em>α</em>) of these intervals would consist the true parameter value.
The 92% confidence interval for the mean annual phone charge of all Vopstra customers is:
This confidence interval implies that true mean annual phone charge of all Vopstra customers is contained in the interval ($405, $535) with 0.92 probability.
Thus, the correct option is (a).