stats

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.

  1. 👍 0
  2. 👎 0
  3. 👁 436
asked by GLEN
  1. I'll give a few hints and let you take it from there.

    Hypotheses:
    Ho: µ ≥ 26
    Ha: µ < 26

    Try a z-test to determine the test statistic.

    Formula:
    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.

    1. 👍 0
    2. 👎 0
  2. t-test is used because it is quantitative, z-test is used for categorical for these type of stats.

    1. 👍 0
    2. 👎 0
    posted by Roxanne
  3. 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
    tcdf(p-value, 99,df)

    Step 4: reject or not reject null hypothesis

    1. 👍 0
    2. 👎 0
    posted by Roxanne

Respond to this Question

First Name

Your Response

Similar Questions

  1. langauge arts

    What is the best way to rewrite the following topic to form a focused thesis statement? Electric cars vs. Cars fueled with gasoline A. Cars fueled with gasoline shouldn't be allowed on the road, especially when electric cars are

    asked by Grace on April 10, 2015
  2. stats

    A company with a large fleet of cars found that the emissions systems of 18 out of the 65 randomly selected cars they tested failed to meet pollution control guidelines. Is this strong evidence that more than 20% of the fleet

    asked by Erica on May 11, 2011
  3. Math

    3. The costs of doing business for a company can be found by adding fixed costs, such as rent, insurance, and wages, and variable or suppliers costs, which are the costs to purchase the product you are selling. The portion of the

    asked by adb on January 19, 2011
  4. english

    2. Which of the following is the best reason to use visuals in a research presentation? A)) to illustrate your main point in an engaging manner B)) to illustrate any topic with data in percentages C)) to show different ways of

    asked by dd on April 6, 2015
  5. math

    A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is

    asked by nina on April 27, 2018
  6. math

    A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is

    asked by Anonymous on November 30, 2015
  7. math

    A company has a policy of retiring company cars; this policy looks at number of miles driven, purpose of trips, style of car and other features. The distribution of the number of months in service for the fleet of cars is

    asked by john on November 30, 2015
  8. maths, statistics

    The yearly mileage accumulated by an automobile in a large car rental company’s fleet is normal with mean 18000 kilometres and standard deviation 1700 miles. At the end of the year the company sells 80% of its cars, keeping the

    asked by eimear on April 3, 2017
  9. Algebra

    The costs of doing business for a company can be found by adding fixed costs, such as rent, insurance, and wages, and variable costs, which are the costs to purchase the product you are selling. The portion of the company’s

    asked by Kris on August 4, 2008
  10. algebra

    The costs of doing business for a company can be found by adding fixed costs., such as rent, insurance, and wage, and variable costs, which are the costs to purchase product you are selling. The portion of the company's fixed

    asked by plz help on May 22, 2012

More Similar Questions