Posted by GLEN on Wednesday, July 13, 2011 at 10:11am.
A company with a large fleet of cars hopes to keep gasoline costs down and sets a goal of attaining a fleet average of at least 26 miles per gallon. To see if the goal is being met they check the gasoline usage for 50 company trips chosen at random, finding a mean of 25.02 mpg and a standard deviation of 4.83 mpg. Is this strong evidence that they have failed to attain their fuel economy goal?
A.) Write appropriate hypothesis
B.) Are there necessary assumptions to make inferences satisfied?
C.) Describe the sampling distribution models of mean fuel economy for samples like this.
D.) Find the P- Value
E.) Explain what the p-vale means in this context?
F.) State an appropriate conclusion.
- stats - MathGuru, Wednesday, July 13, 2011 at 6:17pm
I'll give a few hints and let you take it from there.
Ho: µ ≥ 26
Ha: µ < 26
Try a z-test to determine the test statistic.
z = (sample mean - population mean)/(standard deviation divided by the square root of the sample size)
With your data:
z = (25.02 - 26)/(4.83/√50)
Finish the calculation.
Once you have the z-test statistic, check a z-table for the p-value. The p-value is the actual level of the test statistic.
Determine your conclusion. If the null (Ho) is not rejected, there is no difference. If the null is rejected, accept Ha and conclude a difference.
I hope this will help.
- stats - Roxanne, Friday, August 7, 2015 at 10:46pm
t-test is used because it is quantitative, z-test is used for categorical for these type of stats.
- stats - Roxanne, Friday, August 7, 2015 at 10:54pm
Step 1: Hypotheses:
Ho: µ ≥ 26
Ha: µ < 26
Step 2: One sample T- test
t = (ȳ - µ) / (s/√ n)
Step 3: P- Value method
Step 4: reject or not reject null hypothesis
Answer This Question
More Related Questions
- stats - A company with a large fleet of cars found that the emissions systems of...
- Quantitative methods - Hostis sent a car company charges 45 dollars per day plus...
- Math - Ms.abbot went on a road trip. The trip was 792 miles and the average ...
- stats - A random sample of mid-sized cars tested for fuel consumption gave a ...
- Business Statistics 2 - A consumer research group is interested in testing an ...
- Math - How much would it cost to drive an automobile that averages 22 miles per ...
- math - A saleman operates a car which averged 15 miles to a gallon of gasoline....
- math - How much would it cost to drive 54.2 miles in a car that gets 16 miles ...
- math - A company has a policy of retiring company cars; this policy looks at ...
- statistics - A consumer group is testing a manufacturer’s claim that a new car ...