A university health services physician is concerned about how much sleep freshman are getting. She asked a simple random sample of 100 students if they got at least 8 hours of sleep the previous night. then she constructs a 90% confidence interval for the true proportion of all freshman college students who got at least 8 hours of sleep the previous night. Explain what would happen to the width of the interval if the sample size would decrease to 25 students

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A: Given,sample size(n)=100sample proportion(p^)=0.171-p^=1-0.17=0.83α=1-0.90=0.1α2=0.05Z0.05=1.645

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A: It is given that, x is 311 and n is 400.

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Q: A survey of 700 non-fatal accidents showed that 167 involved uninsured drivers. Construct a 99%…

A: Given data,n=700x=167Point estimate isp=xn=167700=0.2386Construct a 99% confidence interval?

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A: It is given that sample size (n) is 80 and the number of students would take the final examination…

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A: Solution: Given information: n= 296 Sample size  x= 114 successes p^=xn=114296=0.3851 Sample…

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Q: Insurance companies are interested in knowing the population percent of drivers who always buckle up…

A: Solution

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Q: one with a 95% confidence level and the other with a 99.7% confidence level. Which interval is…

A: Confidence interval is probability, which refers that population parameter will fall within set of…

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A: Given: Number of students that hated the online math course (y) = 324 Number of students (n) = 400…

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A: As per honor code, we will only answer first question: 1)  p=0.52 n=84, p^=0.42 Use the formula of…

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A: n = 800p^ = 0.1595% CI for p = ?

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A: From the provided information,A survey of 300 women shoppers found that 17% of them shop on impulse.…

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A: Solution: Let X1 be the number of noncoffee drinkers who have trouble sleeping, n1 be the sample…

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A: Mean = 56.64 Standard deviation = 14.598 n=100

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A: Given that, X = 105 N = 300 90% confidence level

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A: DETAILED SOLUTION IS PROVIDED BELOWExplanation:

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A: Given data, n=260 p=18.46% =0.1846 z-value at 98% confidence is Zc=2.326

Q: Assume a nationwide random survey of 800 adults asked about attitudes toward “alternative medicine”…

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Q: university health services physician is concerned about how much sleep freshman are getting. She…

A: Given that She asked a simple random sample of 100 students if they got at least 8 hours of sleep…

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A: To find the 95% confidence interval for the true proportion of all American adults who feel that…

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A: A researcher gathered a sample of participants who volunteered for a studying of phobias. She…

Q: A random survey of 150 CBC students found that 35 of them intended to transfer to WSU Tri-Cities…

A: