A physical therapist wants to determine the difference in the proportion of men and women who participate in regular sustained physical activity. What sample size should be obtained if he wishes the estimate to be within three percentage points with 95​% confidence, assuming that ​(a) he uses the estimates of 21.4​% male and 18.1​% female from a previous​ year? ​(b) he does not use any prior​ estimates?   (a) n=___ (b) n=___

Q: A simulation was done to produce sample means for a particular population. If the mean of the…

A: Checking the Options: Option 1: A sample mean of 10.5 and 18.3For…

Q: The Wechsler IQ test is designed so that the mean is 100 and the standard deviation is 15 for the…

A: It is given that confidence level is 0.99, standard deviation is 15 and margin of error E is 4.

Q: A reporter wants to estimate the proportion, p, of local residents who are in favor of curbside…

A: 95% confidence interval for PMargin of error : E = 0.04No prior estimate for p ; use Required sample…

Q: Data from a representative sample were used to estimate that 31% of all computer users in a recent…

A: The preliminary estimate is, p=31%=0.31The defined margin of error is, E=0.05Since the level of…

Q: An optometrist wishes to know the proportion of patients who undergo laser eye surgery who end up…

A:

Q: Suppose that you are interested in the number of people in each household in the U.S. Your sample…

A: (A) It should be wider than the 95% CI of Q5.Explanation:We need to consider the concept that higher…

Q: survey is planned to determine what proportion of high-school students in a metropolitan school…

A: * SOLUTION :-  From the given information the calculations are shown below

Q: In order to have the standard error of the mean be 13, what from a normally distributed population…

A: From the provided information, Standard error (SE) = 13 Population standard deviation (σ) = 65

Q: Suppose an economist wishes to estimate the mean commute time, , of all people in the civilian labor…

A: We have to find sample size...

Q: Based on historical data at Oxnard College, we believe that 30% of freshman do not visit their…

A: Given Margin of error=E=0.05

Q: Response to allergen inhalation in allergic primates. In a study of 12 monkeys, the standard error…

A: From the provided information, Sample size (n) = 12 Standard error (SE) = 0.4

Q: The Congressional Budget Office reports that 36% of federal civilian employees have a bachelor's…

A: Note:Thank you for posting the question! Since your question has more than 3 parts, we have solved…

Q: Which critical value would you use to estimate a population mean from a sample of size 15 with 99%…

A: Solution-: Given: n=15, c=0.99 We want to find the critical value to use to estimate a population…

Q: The electric cooperative needs to know the mean household usage of electricity by its non-commercial…

A: Givenmargin of error(E)=0.09Variance(σ2)=1.96standard deviation(σ)=1.96=1.4confidence level=80%

Q: The average starting salary of individuals with a master's degree in statistics is normally…

A:

Q: If you have a population standard deviation of 10 and a sample size of 4, what is your standard…

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

Q: If you want to be 99% confident of estimating the population mean to within a sampling error of ±6…

A: Obtain the sample size needed.   The sample size needed is obtained below as follows : Use EXCEL…

Q: When we are calculating variance (or standard deviation) for a sample and intend to use it as an…

A: Given information: s=∑xi-x¯2N-1s2=∑xi-x¯2N-1

Q: The sample size required is (Round up to the nearest integer.)

A: Here use formula of margin of error

Q: Suppose that the amount of time per day that American adults spend on their mobile devices is…

A: From the provided information, Mean (µ) = 229 Standard deviation (σ) = 57

Q: You would like to construct a 90% confidence interval to estimate the population mean score on a…

A: Given that the sample mean x¯ = 513 Sample standard deviation S = 76

Q: A company wants to estimate the mean number of hours per week adults use computers at home. What is…

A: From the provided information, Population standard deviation (σ) = 1 Confidence level = 95% Margin…

Q: In order to estimate the difference between the average miles per gallon of two different models of…

A: It is required to obtain the 95% confidence interval estimate of the difference between the average…

Q: If you want to be 99% sure confident of estimating the population mean to within a sampling error of…

A: The critical value from the standard normal table at 99% confidence level is,

Q: The water works commission needs to know the mean household usage of water by the residents of a…

A: The margin of error is 0.13 and the variance is 2.56.

Q: You would like to construct a 90% confidence interval to estimate the population mean score on a…

A: a) Sample mean is best point estimate of population mean So best point estimate = 502.

Q: What sample size should be used in a study conducted to estimate the average monthly absences of…

A:

Q: Of 1091 randomly selected cases of lung cancer, 801 resulted in death within 10 years. How large…

A: To Calculate: How large must the sample be ?

Q: An independent samples study exhibted the following sample characteristics: Sample 1, n = 54 with a…

A: Given that: Sample 1: n1 = 54 with a sum of squared deviations (SS1) = 311.6. Sample 2: n2 = 57 with…

Q: 3. What sample size should be chosen to find the mean number if absences per month for school…

A: GivenMargin of error(E)=0.20confidence level=90%Variance(σ2)=1.21standard deviation(σ)=1.21=1.1

Q: Suppose you take a sample of size 60 from a Normal distribution with  population mean (mu) 412 and…

A:

Q: 1. If the standard deviation for a set of numbers equals 15, what is the variance for the same…

A: Hey there! Thank you for posting the question. Since there are multiple questions posted, we will…

Q: If random samples, each with n = 16 scores, are selected from a normal population with µ = 100 and σ…

A: Here, the known values are n = 16 scores, µ = 100 and σ = 20.

Q: Suppose that you are interested in the number of people in each household in the U.S. Your sample…

A: C. It should be narrower than the 95% CI. Explanation:99% intervalz= 99%= 2.576n=10x̄=2.5σ=1.2…

Q: You wish to evaluate the differences in educational quality between two training centres (A and B).…

A:

Q: An ecologist is studying the impact of local polluted waters on the growth of alligators. The length…

A: Length of adult male alligators follows a normal distribution with µ and standard deviation 2. n…

Q: Suppose that in a large population of students, the mean amount of sleep the previous night was ? =…

A: Solution

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

A:

Q: Data from a representative sample were used to estimate that 33% of all computer users in a recent…

A: P=0.33E=0.04