Aresearcher did a pilot sample of 25 individuals with a population standard deviation of 0.40. How many more must he survey to develop a 95% confidence interval that has 0.03 margin of error? (Note: Round - up your answer into whole number) A 543 B 518 658 D 683

Q: A sample of 28 was taken from a population, and r = .45. What is the 95% confidence interval for the…

A: Correlation coefficient: Correlation analysis is used to measure strength of the association between…

Q: Find the value of t a/2 for a 99% confidence interval when the sample size is 30

A: Given Confidence = 99% n=30

Q: In a survey, the planning value for the population proportion is  p* = 0.33.  How large a sample…

A: It is given that the population proportion is 0.33.It is known that the critical value for 95%…

Q: In order to infer on the mean height of children in a school , a sample of 36 students were…

A: Obtain the standard error for the sample mean. The standard error for the sample mean is obtained…

Q: If we want to provide a 95% confidence interval for the mean of a population when the population…

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Q: To estimate the average gestation time (time being carried in the womb between conception and birth)…

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Q: A 95% confidence interval for the mean hours freshmen spent on social media per day was calculated…

A: Solution: From the given information, the 95% confidence interval for the mean hours freshmen spent…

Q: #7. On the verbal section of the SAT, the standard deviation is known to be 100. What size sample…

A: Introduction: The 100 (1 – α) % confidence interval for the population mean, μ, when the population…

Q: A researcher wants to construct a 98% confidence interval for the proportion of elementary school…

A:

Q: Which of the following would result in the narrowest confidence interval? O A sample size of 30 with…

A: Given, The values of α and n.

Q: Campus athletics is interested in the proportion of registered students living on campus who play…

A: The 95% confidence interval is (0.12, 0.18).

Q: The General Social Survey asked: “How many e-mails do you send in a day?” The results of 928…

A: Given information Sample size n = 928 Mean x̅ = 10.4 Standard deviation s = 28.5 Since significance…

Q: The owner of the AGT Gas Station wishes to determine the fraction of customers who pay using a…

A:

Q: Which of the following would result in the narrowest confidence interval? A sample size of 100 with…

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Q: Find the sample size needed for a confidence interval about the population proportion if you want a…

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Q: Which of the following confidence intervals would have a wider width for the same set of data? A 90%…

A: We have find which confidence interval have a wider..

Q: Which of the following confidence intervals would have a wider width for the same set of data? A 90%…

A: which of the following confidence intervals would have a wider width for the same set of data?…

Q: An agriculture publication daims that the population mean of the birth weights for all Alpine goats…

A:

Q: The statistics department is interested in estimating the proportion of students who have majored in…

A: Here we need to find the required sample size to estimate the proportion of students who majored…

Q: In a sample of 22 people, the average cost of a cup of coffee is $2.83. Assume the population…

A: Given data: Sample size  = 22 Mean = $2.83 standard deviation =  $1.01 Confidence level  = 90% To…

Q: In a survey, the planning value for the population proportion is p* = 0.25. How large a sample…

A:

Q: Which of the following would result in the narrower confidence interval?

A: Note: The confidence interval with small confidence level has the narrower confidence interval. The…

Q: In a sample of 30 people, the average cost of a latte is $3.82. The standard deviation for the…

A: Given : n = 30 x¯ = 3.82 s = 1.66 Confidence level = 99%

Q: For a height study of silicon nanopillars on a silicon membrane flat, a sample n = 50 is used,…

A: Given that, Mean X bar = 305.58 And Variance= 1366.86 And sample size, n= 50 Z at 95% level of…

Q: The amount of material used in making a custom sail for a sailboat is normally distributed with a…

A: Confidence interval is a range of values it contains the true population parameter with specified…

Q: An electrical firm manufactures light bulbs for LCD projectors. A randomly selected sample of 24…

A: We have given that,  Sample mean (x̄) = 600 hours, standard deviation (s) = 50 hours , sample size…

Q: Which of the following would result in the narrowest confidence interval? O A sample size of 30 with…

A: The confidence interval depends on the three factors: Confidence level: The width of the confidence…

Q: A 99% confidence interval for a population mean was reported to be 140 to 150. If population…

A: It is given that the 99% confidence interval for a population mean is 140 to 150. The population…

Q: You are doing a class project for Stat 1, and do not have enough money to sample all mobile home…

A: At 95% confidence level, α=0.05 and z=1.96.

Q: In a survey, the planning value for the population proportion is p* 0.16. How large a sample should…

A: Obtain the sample size of a preliminary estimate for p is 0.16 with the 90% confidence.   The…

Q: What is the critical t-value for finding a 95 percent confidence interval estimate from a sample of…

A: Given: Sample size (n)=18 Confidence level = 95% Level of significance = 1-confidence level = 1-0.95…

Q: For a population data set, σ = 13.0 . How large a sample should be selected so that the margin of…

A: Given, As per z-distribution table, the zcrit value for 96% confidence level is obtained as 2.05.

Q: In a poll conducted, 439 of 1007 adults in a certain country polled said they were "picky eaters."…

A: a. The proportion of the respondents said they were picky eaters is, p^=xn=4391007=0.4359≈0.44 Thus,…

Q: An arborist is interested in determining the mean diameter (in centimeters) of mature white oak…

A: Given: n=7, x=49.09 and s=13.8.   At 95% confidence level, the value of z is 1.96.

Q: Complete the following senteces with the correct answer regarding a confidence interval for the mean…

A: Solution: Let X be the random variable. From the given information, the population standard…

Q: Complete the following senteces with the correct answer regarding a confidence interval for the mean…

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Q: A health professional takes the temperatures of 5 patients:   99.8    98.3    96.9    98.0    98.3…

A: We have given that  A health professional takes the temperatures of 5 patients: 99.8    98.3    96.9…

Q: ch. The "confidence interval" lying between +1 SEM and -1 SEM would give us a “confidence level"…

A: The 68-95-99.7% (Empirical) Rule: For a normal distribution, the empirical rule (68-95-99.7% Rule)…

Q: In a survey, the planning value for the population proportion is p* = 0.25. How large a sample…

A: Given : Population proportion (p*) = 0.25 Confidence level = 95% So ; significance level (α) =…

Q: In a survey, the planning value for the population proportion is p* = 0.25. How large a sample…

A: Given,sample proportion(p*)=0.25margin of error(E)=0.08α=1-0.95=0.05α2=0.025Z0.025=1.96   (from…

Q: Example : In the group of 345 children surveyed, the sample mean was 11.3 and the standard deviation…

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Q: In a survey, the planning value for the population proportion is p* = 0.35. How large a sample…

A: Find z-critical value. Refer Standard normal table/Z-table OR use excel function…

Q: A survey of 32 retail stores revealed that the average price of a microwave oven was $375, with a…

A: Given information- Sample size, n = 32 Significance level, α = 0.001 Sample mean, x-bar = $375…

Q: A study of 4 bolts of carpet showed that their average length was 76.2 yards and the sample standard…

A:

Q: A sample of 64 is taken from a population, with the mean of the sample being 119 and the standard…

A: Option B is correct (113, 125)

Q: A medical devices company wants to know the number of hours its MRI machines are used per day. A…

A: Given information- Population standard deviation, σ = 4 hours Confidence interval = 0.98…