Question

1. The mean lifetime of laptop computers produced by one company is 4.6 years with a standard deviation of 1.1 years. Consider random samples of 55 laptop computers repeatedly taken for 2 weeks. What is the standard deviation of the sampling distribution of the sample means? (If rounding is needed, round to four decimal places).

2 . Suppose that for 18-to-25-year-old men, the mean number of football games watched each football season is 19.0 games with a standard deviation of 3.7 games. If 31 randomly selected men in this age range are surveyed, what is the probability that the mean number of football games watched by this group is no more than 17 games per season? (If rounding is necessary, round to four decimal places).

3 . The Council of Christian Colleges and Universities Tuition Survey claims that in 2011-12 the population standard deviation of tuition and fees at CCU-member colleges was $4,385. If a sampling distribution that has a standard error of the mean equal to $750 is desired, how many CCU-member colleges would need to be in each sample? (round up to the next whole number)

4 . A study on the anxiety level of Americans over the Covid-19 found that the average American has anxiety of 52 (scaled 1-100) with a standard deviation of 7 points. If a sampling distribution is created using samples of size 100 of Americans by state, what would be the mean of the sampling distribution of the sample means? (If rounding is necessary, round to four decimal places).

5 . A study of 5,000 American women was taken to determine the mean number of children per household. Samples of 100 were taken by state. The average American household, as reported by women, contains 2.1 children with a standard deviation of 1.87. Is it safe to assume normalcy for the sampling distribution? Explain

Answer 1

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as per HomeworkLib policy i answered the 1st 2 questions.