My Notes Ask Your Toac An article reported that for a sample of 42 kitchens with

Question

My Notes Ask Your Toac An article reported that for a sample of 42 kitchens with gas cooking appliances monitored during a one-week period, the sample mean CO2 level (ppm) was 654.16, and the sample standard deviation was 164.72 (a) Calculate and interpret a 95% (two-sided) confidence interval for true average CO2 level in the population of all homes from which the sample was selected. (Round your answers to two decimal places.) ppm Interpret the resulting iterval. We are 95% confident that the true population mean lies above this interval. we are 95% confident that this interval contains the true population mean. we are 95% confident that the true population mean lies below this interval. we are 95% confident that this interval does not contain the true population mean. (b) Suppose the investigators had made a rough guess of 175 for the value of s before collecting data. What sample size would be necessary to obtain an interval width of 47 ppm for a confidence level of 95%? (Round your answer up to the nearest whole number) kitchens You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? Submit Answer Save Progress Practice Another Version

Explanation / Answer

Hence 189 Kitchens

CI for 95% n 42 mean 654.16 z-value of 95% CI 1.9600 std. dev. 164.72 SE = std.dev./sqrt(n) 25.41685 ME = z*SE 49.81611 Lower Limit = Mean - ME 604.34389 Upper Limit = Mean + ME 703.97611 95% CI (604.3439 , 703.9761 )

Related Questions

Navigate

• Browse (All)
• Browse M
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.