The monthly earning of a group of business students are normally distributed with a standard deviation of 549 dollars. A researcher wants to estimate the mean monthly earnings of all business students. find the sample size needed to have a confidence level of 95% and a margin of error is 137 dollars.

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Q: A sample of 40 cows is drawn to estimate the mean weight of a large herd of cattle. If the standard…

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Q: In a random sample of twelve ​people, the mean driving distance to work was 21.5 miles and the…

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Q: In a survey, 28 people were asked how much they spent on their child's last birthday gift. The…

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Q: The mean for the verbal component of the SAT is reported as 500, with a standard deviation of 100. A…

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Q: The number of chocolate chips in an 18-ounce bag of chocolate chip cookies is approximately normally…

A: Givenmean(μ)=1252standard deviation(σ)=129

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Q: The SAT scores of all freshmen accepted at State University are normally distributed, with a mean of…

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Q: If the manager of a bottled water distributor wants to​ estimate, with 99​% ​confidence, the mean…

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Q: An advocacy group claims that the mean braking distance of a certain type of tire is 75 feet when…

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Q: In a random sample of ten ​people, the mean driving distance to work was 18.1 miles and the standard…

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Q: If the population standard deviation is 10, how large a sample is necessary to have a standard error…

A: The population standard deviation is 10 and the standard error is less than 5 points.

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 Population standard deviation (σ) = $5…

Q: 900 students were surveyed and had an average GPA of 2.7 with a standard deviation of 0.4. Calculate…

A: Given data,n=900Mean μ=2.7sd σ=0.4Z-value at 95% confidence is Zc=1.96 Calculate the margin of…

Q: In a sample of 90 large grade A eggs, the mean number of calories was 70 with a standard deviation…

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Q: given a standard deviation of + or - 0.023m at the 90% confidence level, what is the 68% error level…

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Q: The waist girth of 2,500 employees in a large company follows the normal distribution with mean of…

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Q: It has been reported that the mean score for a student who takes the certain test is 80 with the…

A: Given mean = 80 standard deviation, σ = 9 sample size, n = 100

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: The standard deviation of a normal distribution is 20. What is the standard error of the mean…

A: from the given information,standard deviation(σ) =20.Sample size(n) = 225.

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A: A sample of 20 randomly selected women with children on the streets of Baltimore and the average…

Q: The head of the quality department of a battery factory needs to estimate the average lifetime of a…

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Q: In a random sample of six ​people, the mean driving distance to work was 24.3 miles and the…

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Q: The admission committee of AUCA enrolls 60% of those who took the exam. If the scores follow a…

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Q: A published study says that 95 percent of American children are vaccinated against measles, with a…

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Q: Suppose that the owner of a recently opened convenience store in Kuala Lumpur, Malaysia, wants to…

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

A: Givensample size(n)=23sample mean (x) = 31standard deviation (s) = 8α = 1-0.95=0.05α2=0.025degrees…

Q: Suppose that the distance of fly balls hit to the outfield (in baseball) is normally distributed…

A: let X be the distance of fly balls hit to the outfield X~N(mu=260,sigma^2=50^2) n=49 we want to find…

Q: In a survey, 21 people were asked how much they spent on their child's last birthday gift. The…

A: Margin of error is the error due to random sampling. The margin of error decreases with increase in…

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Q: The manager of Tee Shirt Emporium reports that the mean number of shirts sold per week is 1,210,…

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Q: In a recent sample of 89 used cars sales costs, the sample mean was $6,225 with a standard deviation…

A: Given, Sample size = 89 Sample mean = 6225 Sample standard deviation = 3151   Since the population…

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 order to qualify for police academy training, recruits are given a test of stress tolerance. The…

A: From a given information, Mean = 250 Standard deviation = 18

Q: In a survey, 41 people were asked how much they spent on their child's last birthday gift. The…

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Q: In a random sample of 12 people,the mean driving distance to work was 23.5 miles and the standard…

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Q: In a random sample of eleven ​people, the mean driving distance to work was 18.1 miles and the…

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Q: The admission committee of AUCA passes 33% of those who took the exam. If the scores follow a normal…

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Q: The average credit card debt for a recent year was $8,776. Five years earlier the average credit…

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Q: The director of vehicle maintenance for a large mass transportation authority wants to know the…

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Q: A travel analyst claims that the mean price of a round trip flight from New York City to Los Angeles…

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Q: According to an article in Good Housekeeping, a 128-lb woman who walks for 30 minutes four times a…

A: Given, Sample size = 35 Sample mean = 9.1 Sample standard deviation = 5   Set up the null and the…

Q: If a quality control manager wants to estimate the mean life of light bulbs to within + 21 hours…

A: The margin of error is value by which an estimated value of population parameter can differ from the…

Q: We measure the heights of 57 students and obtain a sample mean of 67 inches and a sample standard…

A: Given information- Sample size, n = 57 Sample mean, x-bar = 67 inches Sample standard deviation (s)…