Suppose that the standard deviation of the tube life for a particular brand of TV picture tube is known to be σ=400, but that the mean operating life is not known. Overall, the operating life of the tubes is assumed to be approximately normally distributed. For a sample of n =15, the mean operating life is X ̅=8900 hr. Determine (i) the 95 percent and (ii) the 90 percent confidence intervals for estimating the population mean.

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Q: How large a sample should be selected to provide a 90% confidence interval with a margin of error of…

A:

Q: How large a sample should be selected to provide a 99% confidence interval with a margin of error of…

A: Given,standard deviation(σ)=50margin of error (E)=10α=1-0.99=0.01α2=0.005Z0.005=2.58

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Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of automobiles, a…

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A: Solution

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Q: To compare the dry braking distances from 30 to 0 miles per hour for two makes of​ automobiles, a…

A: we have given that  n1=35 ,n2=35 ,xbar =43,  xbar =44 ,sigma1=4.7 and sigma2=4.5   Note : according…

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A:

Q: 1. Miss Romero noted that the mean scores of a random sample of 15 Grade 8 students who had taken a…

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

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A: given that,sample mean, x =9standard deviation, s =3.3sample size, n =9

Q: At α=0.10​, can the engineer support the claim that the mean braking distances are different for the…

A: For make A, sample size n1 = 35, sample mean = 40 and population SD = 4.8 For make B, sample size n2…

Q: Suppose that the standard deviation of the tube life for a particular brand of TV picture tube is…

A: It is given that , the standard deviation of the tube life for a particular brand of TV picture tube…

Q: A random sample of 100 observations produced a mean x̅ =38.5 and a standard deviation of 3.2. find a…

A: Given information Sample size(n) = 100 Sample mean x̅ =38.5 Sample standard deviation = 3.2…

Q: A researcher claims that the mean sodium content of sandwiches at Restaurant A is less than the mean…

A: n1 = 22n2 = 28   x1 =670x2 = 690 s1 = 20s2 = 30

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A: Given σ=0.14E=0.11n=?The z-value at 99% confidence is 2.58

Q: For a sample of size 40 with an unknown standard deviation, the interval estimate at 99% confidence…

A: For a sample of size 40 with unknown standard deviation, the interval estimate at 99% confidence…

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A: It is given that Population SD = 0.26 Margin of error E = 0.15 Level of confidence = 0.95 The…

Q: How large a sample should be selected to provide a 95% confidence interval with a margin of error of…

A: Given that, Confidence Interval = 95% Margin of error, M.E. = 4 Population Standard deviation, σ =…

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Q: If the sample consisted of 80 night students with a GPA of 3.49 and a standard deviation of 0.02,and…

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Q: What sample size is needed to estimate a population mean within t 70 of the true mean value using a…

A: According to the provided information, Population standard deviation (σ) = 140.625 Confidence level…

Q: In a random sample of six ​people, the mean driving distance to work was 23.2 miles and the standard…

A: We have given that  Sample size n =6 Sample mean = 23.2 Standard deviation =6.4

Q: In what range would you expect to find the middle 98% of amounts of nicotine in these cigarettes…

A: The variable x1 be the lower amount of nicotine in the cigarette, and variable x2 be the upper…

Q: The sample size needed to estimate a population mean within 2 units with a 95% confidence when the…

A: Given,σ=8E=2Zc at 95% confidence is Zc=1.96n=?

Q: How large a sample should be selected to provide a 99% confidence interval with a margin of error of…

A:

Q: Suppose the standard deviation of the losses had been $3600 instead of $1800. What would the larger…

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Q: Suppose that for a random sample of 250 firms that revalued their fixed assets, the mean ratio of…

A: Sample Mean 1 (\bar X_1)(Xˉ1​) = 0.6290.629 Sample Standard Deviation 1 (s_1)(s1​) = 0.1770.177…

Q: Suppose the population standard deviation is standard deviation "sigma"=7, an SRS of n=45 is…

A: Given that, σ=7,n=45 Critical value: Using the z-table, the critical value at 95% confidence level…

Q: me that the heights of women are normally distributed with a mean of 62.9 inches and a standard…

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Q: When the population standard deviation is unknown and the sample size is greater than 30, what table…

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A: The provided information are:

Q: o compare the dry braking distances from 30 to 0 miles per hour for two makes of​ automobiles, a…

A:

Q: Find the 90% confidence interval for the variance and standard deviation of the ages of students at…

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Q: Suppose that a simple random sample is taken from a normal population having a standard deviation of…

A: Given, n=64 σ=5.5α=0.05MOE=Zα/2*σn

Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.