The average price of a gallon of unleaded regular gasoline wasreported to be $2.

Question

The average price of a gallon of unleaded regular gasoline wasreported to be $2.34 in northern Kentucky (The CincinnatiEnquirer, January 21, 2006). Use this price as the populationmean, and assume the population standard deviation is $.20. Calculate the sample size necessary to guarantee at least .95probability that the sample mean is within $.03 of the populationmean (0 decimals). The average price of a gallon of unleaded regular gasoline wasreported to be $2.34 in northern Kentucky (The CincinnatiEnquirer, January 21, 2006). Use this price as the populationmean, and assume the population standard deviation is $.20. Calculate the sample size necessary to guarantee at least .95probability that the sample mean is within $.03 of the populationmean (0 decimals).

Explanation / Answer

mean, = 2.34 standard deviation, = 0.20 sample size, n = ?? standard error, e = /n sample mean, x = 0.03 for 0.95 probability, z = 1.65 z = (x-)/e hence 1.65 = (0.03-2.34)/e hence e = -1.4 now e = /n hence -1.4 = 0.20 / n hence n = -0.143 hence, n = 0.021

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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