A survey of 25 randomly selected customers found the ages shown (in years). The mean is 33.56 years and the standard deviation is 9.42 years a) Construct a 80% confidence interval for the mean age of all customers, assuming that the assumptions and conditions for the confidence interval have been met b) How large is the margin of error? c) How would the confidence interval change if you had assumed that the population standard deviation was known to be 10.0 years? a) What is the confidence interval? (Round to two decimal places as needed.) 37 39 21 31 26 27 36 35 38 44 48 21 20 38 28 17 29 48 40 37 34 19 48 34 44

Q: A 93.32% Cl is given as (2.5, 3.5). From this information, find a 95% confidence interval (yes, this…

A: The provided information is as follows:The 93.32% confidence interval is (2.5,3.5).

Q: the lengths of pregnancies in a small rural village are normally distributed with a mean of 270 days…

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Q: A confidence interval was found to be (2.4, 7.9). What was the point estimate? O A. 5.27 O B. 5.2 O…

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Q: Suppose that a certain brand of light bulbs has a mean life of 600 hours and a standard deviation of…

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Q: If n=13, (x-bar)=48, and s=12, construct a confidence interval at a 95% confidence level. Assume the…

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Q: 9. Answer parts a-d. What is the point estimate of the population mean? 8.38 .. Find the standard…

A: We have given that,  Sample size (n) = 532, mean (x̄) = 3.38 and standard deviation (s) = 1.9

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Q: Construct the indicated confidence interval for the population mean . Assume c = 0.98, = 101.3, =…

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Q: A history teacher records the SAT scores of all 87 of her students. The data is used to construct a…

A: For calculating the confidence interval, we need to satisfy the following conditions: Independence…

Q: The lengths of pregnancies in a small rural village are normally distributed with a mean of 263 days…

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Q: many samples) gave a mean date of ?1 = year 1261 with standard deviation ?1 = 38 years. At a second,…

A: The z score formula: Now, for z 1 : z1 = ( 1207 − 1261 ) 38   =− 1.42

Q: Construct the confidence interval for the population mean y. C= 0.90, x=16.6, o= 10.0, and n= 80

A: Here, C=0.90, x=16.6, σ=10.0, and n=80.

Q: If X 121, o =27, and n 38, construct a 95% confidence interval estimate of the population mean, u.…

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Q: A random sample of monthly income yielded the data below. x¯=$2400s=$400n=131x¯=$2400s=$400n=131…

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Q: Suppose that another sample of resting heart rates for five Math students was obtained: 72, 68, 66,…

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Q: . A sample of 84 WCC students found mean age 24.7 years old with standard deviation 7.9 years old.…

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Q: If n = 15, the sample mean = 150, SD = 10, what is the confidence interval (using 99% confidence…

A: Given data,n=15x=150σ=10z-value at 99% confidence is Zc=2.576

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Q: If n = 380 and X = 304, construct a 95% confidence interval for the population proportion, p. Give…

A: Given: n = 380 x = 304

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Q: If X= 102, o=9, and n=63, construct a 95% confidence interval estimate of the population mean, μ.

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A: Introduction: It is required to find the limits separating the significantly lower and higher…

Q: It took an average of 4.4 years for a grove of 57 orange trees to bear fruit. Assume the standard…

A: Solution-: Given: x¯=4.4,n=57,σ=3.7,α=0.04 We find 96% C.I. =?

Q: Which type of confidence interval should you use in this situation? A sample of 6 adult elephants…

A: It is given that Mean = 12200Sample std. deviation = 200Sample size = 6Confidence level = 95%

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Q: If n = 220 and X = 176, construct a 95% confidence interval for the population proportion, p. Give…

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Q: For men heights are normally distributed with a mean of 69 inches and a standard deviation of 2.8…

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Q: A grocer finds that the cantaloupes in his store have weights with mean 0.7 kg and standard…

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Q: If X=96​, σ=9​, and n=63​, construct a 99​% confidence interval estimate of the population​ mean, μ.

A: x¯ = 96σ = 9n = 63construct 99% ci for μ.

Q: If n=21, (x-bar)=37, and s=3, construct a confidence interval at a 90% confidence level. Assume the…

A: Given Information: Sample size n=21 Sample mean x¯=37 Sample standard deviation s=3 Confidence level…

Q: If n = 220, p-hat = 0.4, then what will be the 90% Confidence Interval for the population…

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Q: (a) Starting with the 75% estimate for Italians, how large a sample must you collect in order to…

A: The method of Sample Size and margin of error will be used: In a confidence interval, the range,…

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A: The 90% confidence interval is (62.27, 129.73).Explanation:(1−α)100% confidence interval for μ will…

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A: Given : mean = μ = 20.7 Standard deviation = σ = 1.8 Sample size = n = 16

Q: If n = 20, the sample mean = 250, SD = 15, SEM = 3.354, what is the confidence interval (using 95%…

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