QUESTION 9 A population has a standard deviation of 8. What is the minimum sample size needed to estimate a mean to within 2 units with 66.8% confidence? O A. 13 O B. 15 O C. 14 O D. 12 O E. 16 QUESTION 10 should be used for an 78.7% confiden 'a12 A sample of 40 is taken from a population where the population standard deviation is known to be 5. What z estimate of the mean, rounded to five decimal places? O A. 1.24518 O B. 1.24526 OC 124541

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A: We first find the critical value for 95% confidence interval

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A: Given: Sample size, n=40 Sample mean,x¯=230000sample sd,s=6851

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A: Note: Please repost 5th question as i can answer only 1 question as per my policy. Given data,Mean…

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A: Given Information: Mean = 21 Standard Deviation = 4

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A: 5. Mean = 100, Stdev = 10 a. PX≥140 = PZ≥ 140-100 10 = P(Z≥ 4) = 0.000031

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A:

Q: If a population has a mean of 15 and standard deviation of 3, what is expected of the sample mean…

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Q: A normally distributed population has a population mean ? = 40 and standard deviation ? = 5. What…

A: It is an important part of statistics . It is widely used .

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A: Given: BMI's are normally distributed with mean=26.8 and s.d =7.4

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A: Given Information:  Mean = 100  Standard deviation = 15

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A: Given Standard deviation=σ=23 Confidence level=95% i.e. 100(1-alpha)%=95% Therefore, α=0.05 Allow…

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A: From the provided information,Standard deviation (σ) = 10Sample size (n) = 75

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A: Given,population standard deviation(σ)=10sample size(n)=4

Q: 20. Assume the population standard deviation is o = 25. Compute the standard error of the mean, O7,…

A:

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Q: If the coefficient of variation is 1% and the mean is 3.2, determine standard deviation (to four…

A: We have given that Mean(x̅) = 3.2 CV = 0.01

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A: we know,if a data set has,the mean(μ)  = 48.2the standard deviation(σ)  = 12.5a data value(x) = 33.2

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Q: How large of a sample is required if we want to estimate the mean price of a five year old Corvette…

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A: Hi! Thank you for the question, As per the honor code, we are allowed to answer one question at a…

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A: Given data, Mean=25 sd =2.5 If n=9 P(23<X<26)=?

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A: Given that,  Mean is μ=8.70 Standard deviation σ=2.1546

Q: A given distribution has a population meanof 129 and a population standard deviation, of 12. What…

A: Mean = 129 Standard deviation = 12 Raw score, X = 75