Condence Levels and ZScores ' Confidence Level ' 90% ' 95% 99% ZScore ' 1.65 ' 1.96 2.57 Confidence Interval Formula: itz- L H .Considering any data set, which of the following changes would you expect if the sample size increased but all other values for the data were unchanged? 0 Wider margin of error 0 Cannot be determined without knowing the precise data. 0 Narrower margin of error O No change in margin of error .Conslderlng any data set, which of the following changes would you expect If the condence level were raised but all other values for the data were unchanged? 0 No change in margin of error 0 Cannot be determined without knowing the precise data. 0 Wider margin of error 0 Narrower margin of error .. Believing that their data needs to he more accurate, the researchers from Question 1 survey 300 more adult females for a total of 681 adult females but find their mean is unchanged at 65.2 Inches with a standard deviation that has dropped to 1.9 inches. Construct a confidence interval with the same condence level but with the new sample size and standard deviation. 0 (54.98, 55.41) 0 (55.05, 55.34) O (55.08, 55.32) O (54.33, 55.52) Condence Levels and Z-Scores Confidence Level 90% 95% 99% Z-Score 1.65 1.96 2.57 4. A sample of 500 students at a university is surveyed. 63% are graduate students. What is the margin of error at a 99% condence level? 0 i5.5% O i 4.2% O i3.6% O i2.2% 5. For a survey of 700 people in which 48% show support for an upcoming vote on a proposed constitutional amendment, what would be the margin of error at a 95% confidence level? 0 i1.9% O i4.8% O i3.1% O i3.7% 6. A sample of 300 babies born at a hospital is surveyed. 85%: are born on or after their due date. What is the margin of error at a 90% confidence error? 0 i2.1% O i5.3% O i3.4% O i4.0%