Hanging Toilet Paper: Suppose that you plan to take a random sample of hanging toilet paper rolls in your town, with the goal of estimating the proportions of rolls that are hung so that the paper comes out over the top, as opposed to coming out underneath. You want to determine how many rolls to sample for a 95% confidence interval to have a margin of error no larger than ±.06. The population standard deviation of rolls that are hung so the paper comes out over the top is .43. Determine the necessary sample size.

Q: A random sample of 64 business students required an average of 100 minutes to complete a statistics…

A: Given that, Mean = 100 Standard deviation = 20 Sample size = 64 95% confidence level

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Q: In a random sample of 60​ computers, the mean repair cost was​ $150 and assume that the population…

A: Given: In a random sample of 60​ computers, the mean repair cost was​ $150  the population…

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Q: You randomly select 20 cars of the same model that were sold at a car dealership and determine the…

A: Answer:- Given, Sample size, n = 20  Sample mean, X¯= 9.75  Sample standard deviation, S = 2.39…

Q: Construct the indicated confidence interval for the difference between population proportions p1 -…

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Q: A 95 percent confidence interval for the proportion of parents who use parental controls for…

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Q: A telephone poll of 1,000 adult Americans was reported in an issue of a news magazine. One of the…

A: A telephone poll of 1,000 adult Americans was reported in an issue of a news magazine. One of the…

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A: Hence we are given that; x1=380, n1=1630x2=726, n2=2350 Hence the sample proportions are;…

Q: Construct the indicated confidence interval for the difference between population proportions p1-p2.…

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Q: If the sample mean is 70 and the standard error of the sample mean is 8, what will be the 90%…

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Q: arly-childhood-development studies indicate that the more often a child is read to from birth, the…

A: Answer  Given  X1 =43 n1 =91 x2 =51 n2 =81 Confidence interval =99%

Q: Construct a 95% confidence interval estimate. How does this change your answer to (b)?

A: (d)

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A: Before After 52 47 44 42 40 46 50 43 46 34 38 50

Q: In a random sample of 144 observations, the sample proportion is 0.90. Construct a 95% confidence…

A: given data sample size (n) = 144P^ = 0.9095% ci p.

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A: Given data, p=34%=0.34 n=1750 z-value at 95% confidence is Zc=1.96

Q: 5. At Community Hospital, the burn center is experimenting with a new plasma compress treatment. A…

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Q: In general, would you expect a 90% confidence interval on μ to be longer or shorter than a 95%…

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Q: If n= 220, p-hat= .4, then what will be the 87.4% confidence interval for the population proportion?

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Q: In a random survey of 510 college students, 342 indicated that they have student loan debt.  A…

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Q: We plan to sample parents in order to construct a 99% confidence interval for the proportion who…

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Q: A survey commissioned by the Southern Cross Healthcare Group reported that 16% of New Zealanders…

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Q: company manufactures a certain over-the-counter drug. The company samples 80 pills and finds that…

A: We have given that  Sample size n = 80 Sample mean = 325.5 Standard deviation s=10.3 90%confidence…

Q: What is the effect on a confidence interval if one decreases both sample size and the level of…

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Q: A magazine publisher wishes to determine what proportion of current subscribes will renew. The…

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