Final answer:
To estimate the proportion, you need a sample size of 601 students.
Step-by-step explanation:
To determine the number of samples needed to estimate the proportion of students who were sick at least one time during the semester with a precision of 4% and a 95% confidence level, you can use the formula:
n = (Z^2 * p * (1-p)) / E^2
where:
- n is the required sample size
- Z is the Z-value corresponding to the desired confidence level (1.96 for 95% confidence)
- p is the estimated proportion (0.5)
- E is the desired precision (0.04)
Substituting these values into the formula gives:
n = (1.96^2 * 0.5 * (1-0.5)) / (0.04^2)
n = 600.25
Since the sample size must be an integer, round up the result to the nearest whole number:
n = 601