Textbook example ### Statistical Problems in Lindvall’s Friendship ClubLindvall’s Friendship Club has had members for 50 years as well as new joiners. Lindvall pulls a sample of 25 members and discovers that the sample mean is 30 years with a sample standard deviation of 12 years. **Questions:**a. On what chapter is this problem based? Is there an identical example in that chapter? Report the page number(s) of that example. To what issues does one need to be aware to complete this problem?b. What is the mean of the population?c. What is the standard deviation of the population?d. Develop a 90% confidence interval for the population mean.e. Develop a 99% confidence interval for the population mean.f. Even though the sample mean is 30 years, could the population mean be 35 years at a 90% confidence level?g. Even though the sample mean is 30 years, could the population mean be 20 years at a 99% confidence level?

Name: Textbook example ### Statistical Problems in Lindvall’s Friendship Clu
Uploaded: 2024-03-20T06:38:44.000Z
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Description: Textbook example ### Statistical Problems in Lindvall’s Friendship ClubLindvall’s Friendship Club has had members for 50 years as well as new joiners. Lindvall pulls a sample of 25 members and discovers that the sample mean is 30 years with a sample

Since you have posted a question with multiple sub-parts, we will solve first three sub-parts for you. To get remaining sub-part solved please repost the complete question and mention the sub-parts to be solved. b) For the sampling distribution of mean, the population mean is equal to the sample mean. Therefore, the population mean is 30 years. c) For the sampling distribution of mean, the sample mean is calculated asSample standard deviation, s=σnwhere σ is the population standard deviation Then,σ=sn=1225=12×5=60 Therefore, the population standard deviation is 60 years.d) Since, the sample size is less than 30, use t-value. Here, the degree of freedom=n-1=25-1=24 Andα=1-90%=1-0.9=0.1 So, the value of t at 90% confidence level is 1.711. Then,x±tσn=x±ts=30±1.71112=30±20.532=9.468 , 50.532 Therefore, the 90% confidence interval of population mean is (9.468 , 50.532).