two 95 percent confidence intervals will be constructed to estimate the difference in means of two populations, R and J. One confidence interval, I400, will be constructed using samples of size 400 from each of R and J, and the other confidence interval, I100, will be constructed using samples of size 100 from each of R and J.  When all other things remain the same, which of the following describes the relationship between the two confidence intervals?

Q: All else being equal, a 90% confidence interval will be longer than a 95% confidence interval. True…

A:

Q: If the 95% confidence interval for a population mean from a certain sample is (-6.3, 4.5), then (а)…

A: Given that,95% C.I. for a population mean from a certain sample is (-6.3, 4.5)

Q: If n=14, ¯xx¯(x-bar)=40, and s=4, find the margin of error at a 95% confidence level Give your…

A: Given that, Sample size = 14 Mean = 40 Standard deviation = 4 95% confidence level

Q: Two random samples have sizes of 50 and 25. Which of the following is true for a 99% confidence…

A: Given that  Random sample sizes (n1) = 50  and (n2) = 25 Confidence level (C) = 99%    We know that…

Q: If n = 560 and X = 448, construct a 95% confidence interval for the population proportion, p. %3D…

A:

Q: Based on past data, it is known that about 20.5% of people smoke cigarettes. Suppose we take a…

A: e. Given that p=0.205(20.5%) p^=0.12(12%) n=100 Test statistic: z=p^-pp(1-p)n…

Q: f n = 540 and ˆpp^ (p-hat) = 0.7, construct a 99% confidence interval.Give your answers to three…

A:

Q: f n = 243 and ˆpp^ = 0.267, construct a 95% confidence interval. Give your answers to three…

A: Given, (1-α)100% = 95%  α= 0.05 Zα2 =Z0.025  = 1.96 Using Excel function=NORMSINV(0.025)

Q: If n = 230 and X = 184, construct a 99% confidence interval for the population proportion, p.Give…

A: Given data n = 230 x = 184 sample proportion

Q: If a 95% confidence interval for the difference in two independent means is (-4.5 to 2.1), then the…

A: Point estimate= (-4.5+2.1/2) Point estimate=-2.4/2 Point estimate= -1.2

Q: If n = 180 and X = 144, construct a 90% confidence interval for the population proportion, p. Give…

A: Solution: From the given information, X=144, n=180 and the confidence level is 0.90. The sample…

Q: Suppose you take two SRS from a large population, one of size 800 and one of size 300. If you use…

A: To find: Which will have the smaller margin of error.

Q: If n = 260 and ˆpp^ (p-hat) = 0.45, construct a 90% confidence interval. Give your answers to three…

A:

Q: one city, 79.6% of the 8500 students surveyed said they eat at the school cafeteria. Find the 95%…

A: Given n=8500

Q: If n = 14, ¯x = 50, and s = 3, construct a confidence interval at a 95% confidence level. Assume the…

A: Given information: The sample mean is x-bar = 50. The sample standard deviation is s = 3. The sample…

Q: (True or False)

A: The answer is False.

Q: one with a 95% confidence level and the other with a 99.7% confidence level. Which interval is…

A: Confidence interval is probability, which refers that population parameter will fall within set of…

Q: If n = 330 and X = 264, construct a 95% confidence interval for the population proportion, p. %3D…

A: From the provided information, Confidence level = 95% Sample size (n) = 330, x = 264 Sample…

Q: Two 95 percent confidence intervals will be constructed to estimate the difference in means of two…

A:

Q: If n = 530 and X = 424, construct a 99% confidence interval for the population proportion, p. Give…

A: Given that, n = 530 x = 424 Point estimate = sample proportion =  = x / n = 424 /530=0.8 1 -  =…

Q: If the number of smokers in a sample of 40 students selected from university A is 12 and the number…

A:

Q: If n = 180 and X = 144, construct a 99% confidence interval for the population proportion, p. Give…

A:

Q: If n=360 and X = 288, construct a 95% confidence interval. Give your answers to three decimals < p…

A: It is given that x is 288 and n is 360.

Q: If n = 280 and X = 224, construct a 99% confidence interval for the population proportion, p. Give…

A: Given: X=224n=280 CI=99% Formula: P¯±zα/2P^1-P^n

Q: = 140 and ˆpp^ (p-hat) = 0.7, construct a 90% confidence interval. Give your

A: The value of z at a 90% confidence level is 1.645, which can be obtained by using the standard…

Q: If n=15, ¯xx¯(x-bar)=37, and s=9, find the margin of error at a 80% confidence level Give your…

A: Given that  n = 15 , x- = 37 , s = 9

Q: If n = 440 and X = 352, construct a 90% confidence interval for the population proportion, p. Give…

A:

Q: If n=11, ¯x=37x¯=37, and s=2, find the margin of error at a 95% confidence level Give your answer…

A: The sample size is 11. The degrees of freedom is, df=n-1=11-1=10 The degrees of freedom is 10. The…

Q: By how much must the sample size and be increased if the width of the confidence interval 7.5 is to…

A: The confidence interval for population mean is CI=x¯±zα/2×σn The general formula for width of the…

Q: If n=260 and X = 208, construct a 95% confidence interval. Give your answers to three decimals __…

A: Solution: From the given information, X=208, n=260 and the confidence level is 0.95. The sample…

Q: If n=12, ¯xx¯(x-bar)=49, and s=2, find the margin of error at a 90% confidence level Give your…

A: Given n=12 sample mean=x¯=49 Sample standard deviation, s=2 Confidence interval=90% =0.90 Since, the…

Q: When we regress a variable Y on another variable X, which of the following will NOT lead to a wider…

A: Here use formula of confidence interval of slope coefficient

Q: If a 90%, a 95% and a 99% confidence interval are foung for a population mean, describe how the 3…

A: Population mean CI for known population standard deviation is, CI=x¯±Zσnwhere,σ=population standard…

Q: A 90% confidence interval for the proportion of Americans with cancer was found to be (0.185,…

A:

Q: If x̄=89​, σ=13​, and n=70​, construct a 95​% confidence interval estimate of the population​ mean,…

A:

Q: If n=550 and X = 440, construct a 90% confidence interval. Give your answers to three decimals <p<

A:

Q: If n = 440 and ˆpp^ = 0.52, construct a 90% confidence interval. Give your answers to three…

A:

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

A:

Q: If n=17, ¯xx¯(x-bar)=35, and s=2, find the margin of error at a 95% confidence level Give your…

A: Since population standard deviation is unknown, Use t-distribution to find t-critical value. Find…

Q: suppose that you take 1000 simple random samples from a population and that, for each sample, you…

A:

Q: A confidence interval has been determined  to be -6<u<6, what was the sample mean that was used to…

A: Confidence Interval: Confidence interval is the interval estimate of the population parameter. It is…

Q: If n=15n=15, ¯xx¯=43, and s=20s=20, construct a confidence interval at a 90% confidence level. Give…

A:

Q: A researcher surveys a group of college students to determine the negative life events that they…

A: the given values are n1 = 18n2  = 16  X1 = 42X2 = 48SS1 =398SS2 = 370S21 = SS1n1-1…

Q: If n=14, ¯xx¯(x-bar)=46, and s=6, find the margin of error at a 90% confidence level Give your…

A: We have given that,  Sample mean ( x̄) = 46, standard deviation   (s)=6 , sample size (n) = 14 and…

Q: If X=80​, σ=11​,and n=62​,construct a 95​% confidence interval estimate of the population​ mean, μ.…

A: Given,sample size(n)=62sample mean(x¯)=80standard deviation(σ)=11α=1-0.95=0.05α2=0.025Z0.025=1.96…

Q: If n = 300 and ˆpp^ (p-hat) = 0.95, construct a 99% confidence interval. Give your answers to three…

A: n=300p^=0.95 Confidence level: 1-α=0.99

Q: Ellie and Alec are each attempting to estimate the proportion of coffee drinkers who consume more…

A: Solution Given Ellie’s interval is from 0.286 to 0.514, and Alec’s interval is from 0.346 to 0.474.

Q: If n=25, ¯xx¯(x-bar)=47, and s=3, find the margin of error at a 80% confidence level Give your…

A: Given:  The size of the sample is n=25. The sample mean is given as:…

Q: If n=14, ¯xx¯(x-bar)=47, and s=5, find the margin of error at a 80% confidence level Give your…

A: The degrees of freedom is, df=n-1=14-1=13 The degrees of freedom is 13. Computation of critical…

Q: If n=20, ¯xx¯(x-bar)=46, and s=2, find the margin of error at a 90% confidence level Give your…

A: