The shape of the distribution of the time required to get an oil change at a 20-minute oil-change facility is skewed right. However, records indicate that the mean time is 21.3 minutes, and the standard deviation is 3.6 minutes. Complete parts (a) through (c). (a) To compute probabilities regarding the sample mean using the normal model, what size sample would b required? OA. The normal model cannot be used if the shape of the distribution is skewed right. OB. The sample size needs to be less than equal to 30. OC. Any sample size could be used. OD. The sample size needs to be greater than or equal to 30. (b) What is the probability that a random sample of n = 40 oil changes results in a sample mean time less than 20 minutes? The probability is approximately (Round to four decimal places as needed.) (c) Suppose the manager agrees to pay each employee a $50 bonus if they meet a certain goal. On a typical Saturday, the oil-change facility will perform 40 oil changes between 10 A.M. and 12 P.M. Treating this as a random sample, there would be a 10% chance of the mean oil-change time being at or below what value? This will be the goal established by the manager. minutes. There is a 10% chance of being at or below a mean oil-change time of (Round to one decimal place as needed.)
The shape of the distribution of the time required to get an oil change at a 20-minute oil-change facility is skewed right. However, records indicate that the mean time is 21.3 minutes, and the standard deviation is 3.6 minutes. Complete parts (a) through (c). (a) To compute probabilities regarding the sample mean using the normal model, what size sample would b required? OA. The normal model cannot be used if the shape of the distribution is skewed right. OB. The sample size needs to be less than equal to 30. OC. Any sample size could be used. OD. The sample size needs to be greater than or equal to 30. (b) What is the probability that a random sample of n = 40 oil changes results in a sample mean time less than 20 minutes? The probability is approximately (Round to four decimal places as needed.) (c) Suppose the manager agrees to pay each employee a $50 bonus if they meet a certain goal. On a typical Saturday, the oil-change facility will perform 40 oil changes between 10 A.M. and 12 P.M. Treating this as a random sample, there would be a 10% chance of the mean oil-change time being at or below what value? This will be the goal established by the manager. minutes. There is a 10% chance of being at or below a mean oil-change time of (Round to one decimal place as needed.)
A First Course in Probability (10th Edition)
10th Edition
ISBN:9780134753119
Author:Sheldon Ross
Publisher:Sheldon Ross
Chapter1: Combinatorial Analysis
Section: Chapter Questions
Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...
Related questions
Question
Transcribed Image Text:The shape of the distribution of the time required to get an oil change at a 20-minute oil-change facility is skewed right. However, records indicate that the mean time is 21.3 minutes, and the standard deviation is 3.6 minutes. Complete parts (a) through (c).
(a) To compute probabilities regarding the sample mean using the normal model, what size sample would be required?
A. The normal model cannot be used if the shape of the distribution is skewed right.
B. The sample size needs to be less than or equal to 30.
C. Any sample size could be used.
D. The sample size needs to be greater than or equal to 30.
(b) What is the probability that a random sample of n = 40 oil changes results in a sample mean time less than 20 minutes?
The probability is approximately
(Round to four decimal places as needed.)
(c) Suppose the manager agrees to pay each employee a $50 bonus if they meet a certain goal. On a typical Saturday, the oil-change facility will perform 40 oil changes between 10 A.M. and 12 P.M. Treating this as a random sample, there would be a 10% chance of the
mean oil-change time being at or below what value? This will be the goal established by the manager.
There is a 10% chance of being at or below a mean oil-change time of
(Round to one decimal place as needed.)
minutes.
Expert Solution
This question has been solved!
Explore an expertly crafted, step-by-step solution for a thorough understanding of key concepts.
This is a popular solution!
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 1 images
Recommended textbooks for you
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON
A First Course in Probability (10th Edition)
Probability
ISBN:
9780134753119
Author:
Sheldon Ross
Publisher:
PEARSON