If z = 1.96,the standard deviation is 4.5,and the error is plus or minus $1.75,what is the
Approximate sample size needed for this study?
A)11
B)45
C)14
D)4
E)26

Question

Quizplus · Accepted Answer

The formula for calculating sample size n is:

n = (z^2 * σ^2) / E^2

Where:
z = 1.96 (for a 95% confidence level)
σ = 4.5 (standard deviation)
E = 1.75 (error)

Substituting these values in the formula, we get:

n = (1.96^2 * 4.5^2) / 1.75^2
n ≈ 26

Thus, approximately 26 samples are needed for this study. Therefore, the correct answer is (E).

If Z = 196,the Standard Deviation Is 4