1. The strength of a fiber is normally distributed with a known population standard deviation of 12 kg. An engineer sampled random pieces of fiber, and got the following data: 43, 54, 74.2, 47, 61.6, 80, 38, 40, 32 Find the 96% confidence interval for the mean strength of the fiber.

Q: The average salary of 64 employee was 5400 and the sample standard deviation was 280. Find the 90%…

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Q: Given a sample with s = 8.5 and n = 21. Estimate the population standard deviation with 90% of…

A: Given that Sample size n = 21 Sample SD = 8.5 The critical values of Chi-square at 90% confidence…

Q: Given that the population standard deviation is 5.6, determine the minimum sample size needed in…

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Q: Question 1

A: The formula for the sample size is as follows:

Q: 1. The number of motorcycle sold annually by salespeople is normally distributed with a standard…

A: Note: Please repost remaining questions as i can answer only 1 question as per my policy.   1) Given…

Q: We take a sample of 50 people and obtain a sample mean of 147 pounds with a standard deviation of 15…

A: We have given that  Sample size n = 50 Sample mean = 147 Standard deviation = 15 90%confidence…

Q: 1. The mean and standard deviation for the quality grade point averages of a random sample of 36…

A: "Since you have asked multiple questions, we will solve the first question for you. If you want any…

Q: 9.2 An electrical firm manufactures light bulbs that have a length of life that is approximately…

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Q: If a sample of 25 fish from my pond has mean weight 157 grams with a standard deviation of 8.3 grams…

A: Given: σ = 8.3 grams  n = 25

Q: A confidence interval for the difference between the means of two normally distributed populations…

A: Confidence interval is an inference process which gives the change of plausible values of population…

Q: Given that the 95% confidence interval estimate of the proportion of water specimens that contain…

A: Given  95% CI for population proportion (p) (0.529,0.627)

Q: Determine the sample size needed to construct a 95% confidence interval for the population mean, μ,…

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Q: Given the data from ten (10) randomly selected European females about their foot length. 22.5  24.7…

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Q: A sample of 14 commuters in Cebu showed the average of the commuting times was 33.2 minutes. If the…

A: Sample size : n=14 Sample mean : x¯=33.2 Sample standard deviation : s=8.3 Confidence level :…

Q: 1. Consider the following results for independent samples taken from two populations a. What is the…

A: a. The point estimate of the difference between the two population proportions is,

Q: 13) The number of daily passengers riding in a local Sunshine Cab is assumed to be normally…

A: (a) As the population standard deviation is known, we will use z distribution. At 99% confidence…

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: The daily intakes of milk (in ounces) for ten randomly selected people were: 23.3 28.4 10.5 16.4…

A: Confidence interval: The (1-α) % confidence interval for population standard deviation is given by:

Q: Suppose that Randy is an analyst for the bicyling industry and wants to estimate the asking price of…

A: Sample size, n = 12 Sample Mean, x¯ = 672.46 Sample Standard deviation, s =201.42

Q: If a sample has 20 observations and a 90% confidence estimate for μ is needed, the appropriate…

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Q: 4. A machine produces nails whose lengths are normally distributed with mean u cm and standard…

A: Give: sample size n = 50 Confidence level = 98% Significance level α = 0.02 ∑(x-3)2 = 425 where x is…

Q: 1. The following are body mass index (BMI) scores measured in 12 patients who are free of diabetes…

A: Since you have posted a question with multiple sub-parts, we will solve first three subparts for…

Q: A sample of 30 beams has an average strength of 1908.8 lbs. and s = 327.1. what is the 95%…

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Q: What is the smallest sample size required to provide a 95% confidence interval for a mean, if the…

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Q: A statistician randomly selected 20 classrooms which were used for the recently concluded…

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Q: Which of the following is the minimum sample size necessary to construct a 99% confidence interval…

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Q: he AC breakdown voltage of an insulating liquid indicates its dielectric strength. The following are…

A: Obtain the 95% confidence interval for the true average breakdown voltage. The 95% confidence…

Q: D. The temperature readings for 20 days in Sydney are normally distributed with a mean of 5.5°C and…

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Q: If a school district takes a random sample of 66 Math SAT scores and finds that the average is 480,…

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Q: A random sample of 90 observations produced a sample mean of 25.9 and a sample standard deviation of…

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Q: 1. A company manufactures LCD monitors, which have a lifespan that is approximately normally…

A: The provided information is  x¯=180σ=96n=21α=0.05The critical value is zc=1.96  (from statistical…

Q: A sample of 14 commuters in Chicago showed the average of the commuting times was 33.2 minutes. If…

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Q: In an effort to estimate the mean dollars spent per visit by customers of a food store, the manager…

A: Given: s = $12.30  n = 100

Q: The following information was retrieved from Tennessee Valley Authority system on dissolved oxygen…

A: Given,   Sample size = 20 Sample mean = 3.856 Sample standard deviation = 2.024   Since the…

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: 2. (10%) Given a sample with s = 8.5 and n = 21. Estimate the population standard deviation with 90%…

A: Since you have asked multiple questions we will solve the first question for you. If you want any…

Q: A simple random sample of 5 observations from a normal distribution was taken, and the following…

A:

Q: Q2: Given the samples from normally distributed populations with the unknown standard deviation.…

A: A confidence interval, in statistics, refers to the probability that a population parameter will…

Q: The heights of a simple random sample of 400 male high school sophomores in a Midwestern state are…

A: Given info: The heights of a simple random sample of 400 male high school sophomores in a Midwestern…

Q: A sample data set, n = 115, shows human body temperatures with a mean of 99.6ºF. If the standard…

A: Given Data: n=115x¯=99.6σ=0.75   z-value corresponding to 99% Confidence Interval=2.576

Q: Compute a 95% confidence interval for the true population mean given the following  10 data that…

A: Given, Sample size = 10 Sample mean = 15.3 Sample standard deviation = 3.5   Since the population…

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A: We are required to estimate the interval for the TV watching hours per week from the given sample of…

Q: What is the smallest sample size required to provide a 95% confidence interval for a mean, if it…

A: We want to find the sample size  Given Margin of error=E=1 Standard deviation=σ=3 The critical value…

Q: 8. A sample of seven observation given as; 10 8 13 15 6 8 13 Construct a 98% confidence interval for…

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Q: Suppose the heights of a population of men are normally distributed with an unknown population mean…

A: The provided confidence interval is 90%. The z-value is obtained using Excel.

Q: In a sample of 100 steel canisters, the mean wall thickness was 8.1 mm with a standard deviation of…

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Q: 2. A factory manager collected a sample of ten (10) packets of 3-in-1 coffee and the weights (in…

A: Given data is      25,23,26,28,24,21,26,24,25,27       Sample sizen=10   a)…

Q: A group is interested in seeing if the mean battery life from two different brands of batteries are…

A: The pooled variance is, sp2=n1-1s12+n2-1s22n1+n2-2=19-172+17-110219+17-2=248234=73 The pooled…

Q: The average weight of 35 randomly selected compact automobiles was 2680 pounds. The sample standard…

A: From the provided information, Sample size (n) = 61 Sample mean (x̅) = 2680 Sample standard…