A simple random sample of size n is drawn from a population that is normally dis

Question

A simple random sample of size n is drawn from a population that is normally distributed. The sample mean, x bar, is found to be 105, and the sample standard deviation, s, is found to be 10. (a) Construct a 90% confidence interval about mu if the sample size, n, is 26. (b) Construct a 90% confidence interval about mu if the sample size, n, is 21. (c) Construct an 80% confidence interval about mu if the sample size, n, is 26. (d) Could we have computed the confidence intervals in parts (a)-(c) if the population had not been normally distributed? (a) Construct a 90% confidence interval about mu if the sample size, n, is 26. Lower bound:: Upper bound: (Use ascending order. Round to one decimal place as needed.)

Explanation / Answer

using statdisk

a)

Margin of error, E = 3.349936

90% Confident the population mean is within the range:
101.6501 < mean <108.3499

101.7< mean <108.3

b)

Margin of error, E = 3.76364

90% Confident the population mean is within the range:
101.2364 < mean <108.7636

101.2<x<108.8

c)

Margin of error, E = 2.581567

80% Confident the population mean is within the range:
102.4184 < mean <107.5816

102.4,107.6

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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