Answer:
The upper bound of a 99% confidence interval for the percentage satisfied for all customers in the database is 88.70%.
Explanation:
In a sample with a number n of people surveyed with a probability of a success of
, and a confidence level of
, we have the following confidence interval of proportions.

In which
z is the zscore that has a pvalue of
.
Sample of 252 customers, 208 are satisfied:
This means that

99% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
The upper limit of this interval is:

As a percentage:
100%*0.8870 = 88.70%
The upper bound of a 99% confidence interval for the percentage satisfied for all customers in the database is 88.70%.