Answer
It is 95% certain that between 23% to 31% of all employees in the United States participate in automatic payroll deduction for a 401(k) plan to save for retirement.
Work Step by Step
The descriptive statistics says: "27% of the 1172 employees surveyed ..."
But, this is the percentage of the sample (1172 employees) that is participating in an employer's retirement plan described in the problem text (lines 4 and 5).
For the population there is a margin of error of 4%:
27% - 4% = 23%
27% + 4% = 31%
