A population has standard deviation ? = 21.3. a. How large a sample must be drawn so that a 99% confidence interval for ? will have a margin of error equal to 2.5? b. If the required confidence level were 95%, would the necessary sample size be larger or smaller?   How can this be solved on a Ti84?

Q: A simple random sample of size n=40 is drawn from a population. The sample mean is found to be x…

A:

Q: Suppose we are interested to construct a confidence interval of the mean exam score. A random sample…

A:

Q: A 95% confidence interval for a population mean was reported to be 148.69 to 155.31. If σ = 15, what…

A: given data 95% ci for mean : (148.69,155.31)σ = 15n = ?

Q: A 95% confidence interval for a population mean was reported to be 134 to 142.  If the population…

A:

Q: An IQ test is designed so that the mean is 100 and the standard deviation is 12 for the population…

A: Givenstandard deviation(σ)=12Marign of error(E)=7c=99%α=1-0.99=0.01α2=0.005zα2=z0.005=2.5758   (from…

Q: Suppose a randomly selected sample of n = 50 men has a mean foot length of x = 28.1 cm, and the…

A: given data sample size (n) = 50sample mean ( x¯ ) = 28.1sample standard deviatio (s) = 495% ci for…

Q: Suppose we are interested in a confidence interval for the population mean scores on an exam. A…

A: We have given that,  Sample mean (x̄) = 67.89, population standard deviation (σ) = 9.90 and sample…

Q: Suppose we are interested in a confidence interval for the population mean scores on an exam. A…

A: We have given that,  Sample mean (x̄) = 107.65, population standard deviation (σ) = 4.72 Then,  We…

Q: A study found the temperature of 125 randomly selected healthy adults averaged 98.25 F with a…

A: It is given that sample mean is 98.25 and standard deviation is 0.733.

Q: 4- Suppose that y is N3(4, 41) and let -2 A = %3D -1 3 4. 1 -2 -3 What is the distribution of 9 A9?…

A: Given that y~N3μ, 4𝕀 μ=123  and  A=2-2-4-1341-2-3

Q: Find the 95% confidence interval for the standard deviation of the ages of residents in a senior…

A:

Q: A 95% confidence interval forp is given as (0.34,0.66). How large was the sample used to construct…

A: Formula for the sample size needed to estimate a population proportion is

Q: A 95% confidence interval for a population mean was reported to be 152 to 160. If o = 15. what…

A:

Q: Suppose we are interested in a confidence interval for the population mean scores on an exam. A…

A: We have given that.Sample size (n) = 99Sample mean (x̅) = 95.71Population Standard deviations (σ) =…

Q: You measure 28 turtle's weights, and find, they have a mean weight of 51 ounces. Assume the…

A:

Q: If n=400 and X=160​, construct a 90​% confidence interval estimate for the population proportion.…

A:

Q: Suppose data was collected with n = 36 to compute a 95% confidence interval. If the population…

A:

Q: Find a 90% confidence interval for the population mean age of the Smurfs if a sample of 52 smurfs…

A: It is given that, There is a random sample of size 52 and has a mean of 49.7 and the standard…

Q: when the population standard deviation is 12 points.   b. when the population standard deviation is…

A: It is given that  Sample mean = 68 Sample size = 36 Confidence level = 95%   Note: According to…

Q: A 95% confidence interval for a population mean was reported to be 152 to 160. If s = 15,what sample…

A:

Q: Suppose it is known that approximately 30% of households own a sin- gle TV. Use this to obtain the…

A: From the provided information, The proportion of household own a single TV (p) = 0.30 Margin of…

Q: A study is to be performed to determine a certain parameter in a community. From a previous study a…

A: We have given :  Standard deviation = 46 Sample error = 4 We have to find out n for 99% of…

Q: Suppose we are interested to construct a 95% confidence interval of the mean exam score. A random…

A:

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%

Q: the analysis of a sample for iron content yields a mean result of 35.40% with standard deviation of…

A: Solution

Q: A sample of size n=15 has sample mean "x"=2.1 and sample standard deviation s=1.7. A. Construct a…

A: Given Datan = 15mean µ = 2.1sample standard deviation, s = 1.7 A)95% confidence interval for the…

Q: A 90%  confidence interval for a population mean was reported to be 154  to 160. If standard…

A: Let n be the sample size. Given σ=17 The z-score for 90% confidence is  zα2=1.645

Q: Suppose we gather a random sample of 20 data points. Assume the population standard deviation is 11.…

A: Given,   Sample size = 20 Sample mean = 23 Population standard deviation = 11   Since the population…

Q: If X = 143, o = 29, and n = 35, construct a 95% confidence interval estimate of the population mean,…

A:

Q: If n=400 and X=120​, construct a 90​% confidence interval estimate for the population proportion.…

A: Solution: Given information: n= 400 Sample size  X= 120 Success p^=Xn=120400=0.30 Sample proportion…

Q: You have taken 12 observations from normally distributed data that is known to have a population…

A:

Q: A 95% confidence interval for a population mean was reported to be 152.58 to 159.42. If ? = 15, what…

A: Given:Confidence level = 95%Confidence interval is from 152.58 to 159.42.

Q: Suppose we have data coming from 69 i.i.d observations. The sample mean is JÓ28 and the sample…

A:

Q: Suppose a randomly selected sample of n = 69 men has a mean foot length of x = 28.3 cm, and the…

A: Given that  Sample size n =69 Sample mean =28.3 Standard deviation =3