Answer:
The 99% confidence interval is (0.0787, 0.1613).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of \pi, and a confidence interval 1-\alpha, we have the following confidence interval of proportions.
In which
Z is the zscore that has a pvalue of .
For this problem, we have that:
The survey included 411 adults between the ages of 55 and 64, and 50 of them said that they had used online dating. This means that
The 99% confidence interval is
So , z is the value of Z that has a pvalue of
, so
.
The lower limit of this interval is:
The upper limit of this interval is:
The 99% confidence interval is (0.0787, 0.1613).