Question 276876
We are interested in estimating how many New Jersey residents support moving the New Jersey presidential primary elections up to early February. We were able to draw a simple random sample that includes 400 New Jersey residents. Sixty-five percent of respondents supported the change, with a standard deviation of 40.

 We can be 95% confident that the actual mean in the New Jersey population lies between the ___% and ___%.
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sample p-hat = 0.65
standard error = E = 1.96*sqrt[0.65*0.35/400] = 0.0467
95% CI: 0.65-0.0467 < p < 0.65+0.0467
95% CI: 0.6033 < p < 0.6967
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We can be 99% confident that the actual mean in the population lies between
sample mean = 0.65*400 = 260
standard error = E = invT(0.995,399)*40/sqrt(400) = 2.588*2 = 5.1764
99% CI; 260-5.1764 < u < 260+5.1764
99% CI: 254.82 < u < 265.18
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Cheers,
Stan H.


 ___% and ___%.