The sample mean X is to be used to estimate the mean μ ofa normal distribution with standard deviation 4 inches. Ho...
The distribution of piston diameters is normally distributed with mean μ inches and standard deviation 5 inches. Engineer Dan takes a sample of 25 pistons from the manufacturing assembly line. Let X1, X2, ..., X25 denote these observations which are iid (independently & identically distributed). a.) What is the probability that X-bar, the sample mean of Dan's 25 observations, is within 1 inch of the population mean μ? b.) Suppose engineer Jane decides to take a sample of 30 observations....
Assume that a sample is used to estimate a population mean μ. Use the given confidence level and sample data to find the margin of error. Assume that the sample is a simple random sample and the population has a normal distribution. Round your answer to one more decimal place than the sample standard deviation. 99% confidence; n = 201; x=276; s = 75 answer options 13.8 12.4 16.0 10.5
99 and standard deviation σ A population whose distribution is unknown has mean μ and a sample of size 26 is drawn from this population, then 1, a. The mean oJ a b. The standard error ot c. The distribution of A population whose distribution is unknown has mean μ = 99 and standard deviation σ = 7 and a sample of size 26 is drawn from this population, then 1, a. b. c. The mean of X= The standard...
Suppose an x distribution has mean μ = 4. Consider two corresponding x distributions, the first based on samples of size n = 49 and the second based on samples of size n = 81. (a) What is the value of the mean of each of the two x distributions? For n = 49, μ x = For n = 81, μ x = Suppose the heights of 18-year-old men are approximately normally distributed, with mean 70 inches and standard...
5. Suppose X follows a normal distribution with mean u = 200 and standard deviation o = 40. Find each of the following probabilities. (8 points) a. P(160 < x < 232) b. P(X > 160) C. P(X < 100) d. P(230 < x < 284) 6. Sup Suppose we know that SAT scores have a population average u = 1080 and a standard deviation o = 200. A university wants to give merit scholarships to all students with an...
1. A normal distribution has a mean of μ = 60 and a standard deviation of σ = 12. For each of the following samples, compute the z-score for the sample mean and determine whether the sample mean is a typical, representative value or an extreme value for a sample of this size. a. M = 53 for n = 4 scores σ/ √n= 12/√4 =6 z=(53-60)/6 = -1.17 b. M = 53 for n = 9 scores σ/ √n=...
Assume that x has a normal distribution with the specified mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.) μ = 8; σ = 2 P(7 ≤ x ≤ 11) = Assume that x has a normal distribution with the specified mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.) μ = 6.0; σ = 1.4 P(7 ≤ x ≤ 9) = Assume that x has a normal...
a. Consider a normal distribution with mean 20 and standard deviation 4. What is the probability a value selected at random from this distribution is greater than 20? (Round your answer to two decimal places. b. Assume that x has a normal distribution with the specified mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.) μ = 14.3; σ = 3.5 P(10 ≤ x ≤ 26) = c. Assume that x has a normal...
A population of values has a normal distribution with μ=134.3μ=134.3 and σ=62.4σ=62.4. You intend to draw a random sample of size n=137n=137.What is the mean of the distribution of sample means?μ¯x=μx¯= What is the standard deviation of the distribution of sample means?(Report answer accurate to 2 decimal places.)σ¯x=σx¯=
Assume that a sample is used to estimate a population mean μ . Find the margin of error M.E. that corresponds to a sample of size 7 with a mean of 49.5 and a standard deviation of 6.3 at a confidence level of 90%.