Answer:
Margin of error is the critical value (t score or z score) times the standard error (standard deviation of the sample).
ME = CV × SE
Since n > 30, we can use the z score as the critical value.
Assuming 95% confidence, z = 1.960.
The standard error for a proportion is:
s = √(p (1 − p) / n)
Given p = 0.73 and n = 2035:
s = √(0.73 (1 − 0.73) / 2035)
s = 0.0098
Therefore, the margin of error is:
ME = 1.960 × 0.0098
ME = 0.019
The margin of error is 1.9%. The interval that likely contains the true percent of all people who work out 3 or more days a week is:
73% ± 1.9%
(71.1%, 74.9%)
Step-by-step explanation:
