3.To obtain an estimate of the proportion of 'full time' university students who have a part time job in excess of 20 hours per week, the student union decides to interview a random sample of full time students. They want the length of their 95% confidence interval to be no greater than 0.1. and assume variance is equal to 4. What size sample, n should be taken?

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A:

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

Q: population. The average in the sample was 84.6 with a variance of 400. What is the 90% confidence…

A: Given Data : Sample Size, n = 25 Sample Mean, x̄ = 84.6 sample…

Q: 4. A researcher wants to estimate the mean number of hours per week that a typical person spends…

A: We'll use the formula:n=E2Z2σ2​where:n=sample sizeZ= z-value corresponding to the confidence…

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A: The degrees of freedom for t can be calculated as: DF = n -1 Here, n = number of categories or…

Q: 7. In a survey of 800 people, mean amount of money they spend on movies per month is $48. Using z=…

A: Sample size, n = 800 Mean = 48 Standard deviation = 1.5 Z = 1.96

Q: 3. A sample of n = 25 scores has a mean of M = 200 and a variance of s² = 100. a. Explain what is…

A: Sample is the any fraction of the population. The sampling distribution corresponds to the value of…

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A: Sampling distribution of sample mean(x¯): Suppose simple random sample of size ‘n’ is drawn form any…

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A: From the provided information, Population standard deviation (σ) = 15 Confidence level = 95% Width…

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A: Given Data : Lower limit = 0.224 upper limit = 0.235

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

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Q: 22.) A school counselor is interested in testing if students are showing higher levels of anxiety…

A: as per guideline expert have to answer first question first three sub parts only.  please upload…

Q: 2. Suppose the weight of fish caught from the Santa Monica Pier is normally distributed. From a…

A: Given:true (population) mean µ = 24sample size n =20sample mean x̄ = 22sample variance s2 =…

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: 7. A recent survey of 500 women indicated that 29% of women over age 55 in the study were widows.…

A: Givensample size(n)=500p^=29%=0.29confidence level=90%

Q: 2.  A claim is made that the proportion of adults who text is less than 0.4.  Find the test…

A: Given that  p=0.40 , n=987 , X=398

Q: 1a) Work Time Lost due to Accidents At a large company, the Director of Research found that the…

A: Since your question has multiple sub-parts, we will solve first three sub-parts for you. If you want…

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A:

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Q: What proportion of the distribution of sample means is greater than a z of -1

A: The standard normal variable Z follows normal distribution with mean 0 and standard deviation 1.

Q: 12.A sample of n = 16 scores has a mean of M = 65 and an estimated standard error of 2 points. What…

A: Solution:- Given: n=16, M=65,S.E.=2 We find sample variance (s2)=?

2-Proportion Test

In a 2-proportion test, two separate proportions are measured at the same time, and their similarity is evaluated. It is also known as a 2-proportion z-test, and a comparison of two different proportions is done in this method.