a random sample of 16 flights between Philadelphia and Dallas has an average air

Question

a random sample of 16 flights between Philadelphia and Dallas has an average airfare of $422.10 with a sample standard deviation of $56.30. The 98% confidence interval around this sample mean is
400.99, 443.21 365.80, 478.40 415.06, 429.14 385.48, 458.72 a random sample of 16 flights between Philadelphia and Dallas has an average airfare of $422.10 with a sample standard deviation of $56.30. The 98% confidence interval around this sample mean is
400.99, 443.21 365.80, 478.40 415.06, 429.14 385.48, 458.72 a random sample of 16 flights between Philadelphia and Dallas has an average airfare of $422.10 with a sample standard deviation of $56.30. The 98% confidence interval around this sample mean is
400.99, 443.21 365.80, 478.40 415.06, 429.14 385.48, 458.72

Explanation / Answer

Solution:

We are given

Sample mean = Xbar = 422.10

Sample standard deviation = S = 56.30

Sample size = n = 16

Confidence level = 98%

Degrees of freedom = df = n – 1 = 15

Critical t value = 2.6025

(By using t-table or excel)

Confidence interval = Xbar -/+ t*S/sqrt(n)

Confidence interval = 422.10 -/+ 2.6025*56.30/sqrt(16)

Confidence interval = 422.10 -/+ 2.6025* 14.075

Confidence interval = 422.10 -/+ 36.6299

Lower limit = 422.10 - 36.6299 = 385.48

Upper limit = 422.10 + 36.6299 = 458.72

Confidence interval = (385.48, 458.72)

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

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