The sample size formula in the case of one proportion is \[n=\frac{n\hat{p}(1-\hat{p})}{m^2}\]. In the planning stage for our study, we may not have good knowledge of what to expect for \(\hat{p}\), so we can take a conservative approach to find the minimum sample size needed regardless of what \(\hat{p}\) is. To do this, it turns out that \(\hat{p} = 0.5\) results in the largest sample size. For a 95% confidence interval, this gives us the worst case sample size of

\[n\approx\frac{4*0.5*(1-0.5)}{m^2} = \frac{1}{m^2}\]

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Question prompt

Question:

Question

- The number of courses the student takes this semester:
- The student's height:
- The student's (exact) body temperature:
- The number of siblings the student has:
- The (exact) time the student spends doing school work during a week:
- The number of alcoholic beverages that the student drinks in a typical week:

A
Choice 1

B
Choice 2

C
Choice 3

D
Choice D

E
Choice E

F
Choice F

G
Choice G

H
Choice H