18. Obesity Obesity is defined as a body mass index (BMI) of 30 kg/m² or more. A 95% confidence interval for the percentage of U.S. adults aged 20 years and over who were obese was found to be 22.4 to 23.5%. What was the sample size?

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A: Given : p1:probability of premature delivaries=0.12p2:proportion of normal pregnancies…

Q: In a survey of 3005 adults aged 57 through 85 years, it was found that 81.7% of them used at least…

A: Given :  n = 3005 p̂=0.817

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A: Given that,  σ=8.4,n=77 Critical values: By using the z-table, the critical value at 92% confidence…

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Q: 4. A recent study of 19 students of San Rafael College showed that the mean of the distance they…

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Q: 1. Because of uncertainty in real estate markets, many homeowners are considering remodeling and…

A: given that,sample-1 : (20427 , 27255 , 22115 , 23256 , 21887 , 22786 , 19852 , 23624 , 25885 , 28999…

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Q: In a survey of 3234 adults aged 57 through 85​ years, it was found that 88.9% of them used at least…

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Q: In an effort to estimate the mean amount spent per customer for dinner at a major Atlanta…

A: From the provided information, Sample size (n) = 49 Sample mean (x̅) = $24.80 Population standard…

Q: What is the impact on the confidence interval estimate if a larger sample is used?

A: Confidence interval:

Q: 6. A food snack manufacturer samples 7 bags of pretzels off the assembly line and weighs their…

A: The confidence interval measure the range where the true population parameter exist. If the…

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A: Determine the best point estimate of the population mean. The best point estimate of the population…

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A: Solution: Given information: p = 0.5 Population proportion E= 0.03 Margin of error α=0.10 Level of…

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Q: process control engineer wishes to estimate the true proportion of defective computer chips by using…

A: GivenThe true proportion p=0.01Let the sample size be n.The Z critical value for 90% confidence…

Q: What value of tn-1 would be used to construct a 99% confidence interval for the mean with a sample…

A: Givenconfidence level(c)=99%sample size(n)=17

Q: Find the sample size necessary for an 80% confidence level with a maximal margin of error E= 0.07…

A: Given that s.d =0.34,alpha =0.2,E =0.07 ( e) n= ?

Q: Suppose you are planning to construct a 23% confidence interval for a one sample population…

A: We have given that confidence level (c) = 23% = 0.23

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Q: Find the margin of error for a​ 95% confidence interval for estimating the population mean when the…

A: Sample S.D = s = 110

Q: Suppose our estimate for the mean score for the Player A group was 48 ± 5% SE (standard error). What…

A: Given: Point estimate = 48 Standard error = 5 Confidence level = 95%

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A: According to the provided information, Population standard deviation (σ) = 140.625 Confidence level…

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A: Introduction: A histogram for the apartment sizes in a sample of 48 apartments is given.

Q: 1. How can you make a 95% confidence interval smaller without changing the confidence level?

A: Confidence interval is an interval such that the probability of the unknown parameter to be included…

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A: Data regarding depth penetration of stone tipped versus wooden tipped arrows is given : Wooden…

Q: 1. The mean number of hours of flying time for pilots at Continental Airlines is 49 hours per month…

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Q: 3. Another engineer studies the strength of cables, which has a known population standard deviation…

A: Here we need to obtain the minimum sample size required to obtain a 97% confidence interval.

Q: In a survey, 23 people were asked how much they spent on their child's last birthday gift. The…

A:

Q: In a survey, 19 people were asked how much they spent on their child's last birthday gift. The…

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Q: In a survey of 3116 adults aged 57 through 85​ years, it was found that 86.2​% of them used at least…

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Q: It is known that the population range equals 60. With a 95% confidence level, the sample size that…

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Q: When the population standard deviation is unknown and the sample size is greater than 30, what table…

A: It is clear that the population standard deviation is unknown and the sample size is greater than…

Q: Determine the margin of error for the confidence interval for the mean: 23 +1.7 The margin of error…

A: Confidence Interval is an inference process that is used to estimate the population parameter. The…

Q: 3) A local municipality tests 25 samples of water and finds that the mean concentration of chlorine…

A: Given: Sample size, n = 25            Sample mean, M = 150            Sample SD, s = 18 Since the…

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A: Confidence interval for mean: When the sample size is large (n>30) and population variance (or…

Q: 1. Construct a 90% confidence interval for the proportion of employees requiring size 3.

A: here given  A civil engineering firm issues every new employee with a safety helmet. Four different…

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Q: The determination of copper in a seawater sample gave a mean value of 77.81 mg/L and a ndard…

A: Critical value: The confidence level is 100*(1–α)% = 95%. The critical value is obtained as 1.96…