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.

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

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Q: are vegetarian is 0.078. Find the margin of error for a 99% confidence interval.

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A: Given that  Sample size n =100 Sample mean =8.2 Standard deviation =4.6

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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

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

A: Given It is given that the sample is same and CL is increased from 90% to 95%.

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

A:

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

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

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