Question

A researcher wants to determine the proportion of pro-peace students at Rutgers University. He has no idea what the sample proportion will be. How large a sample is required to be 95% sure that the sample proportion is off by no more than 4% (E)

Answer 1

The sample size is 601.

Step-by-step explanation:

Given information:

Confidence interval = 95%

E = 4% = 0.04

From the z table it is clear that the z-value 95% confidence is 1.96.

A researcher wants to determine the proportion of pro-peace students at Rutgers University.

`p=0.5`

Formula for sample size is

`n=p(1-p)((z)/(E))^2`

Substitute the given values in the above formula.

`n=0.5(1-0.5)((1.96)/(0.04))^2`

`n=0.5(0.5)(49)^2`

`n=600.25`

Sample size can not be a decimal value. So, round the answer to the next whole number.

`n=601`

Therefore, the sample size is 601.