A i have placed my work and my answer on my answer

a) I have placed my work and my answer on my answer sheet.
b) I want to have points deducted from my test for not working this problem.
Question 20
Your answer is CORRECT.
This is a written question, worth 14 points. DO NOT place the problem code on the answer
sheet. A proctor will fill this out after exam submission. Show all steps (work) on your
answer sheet for full credit.
Problem Code: 2023
In a recent publication, it was reported that the average highway gas mileage of tested models of a
new car was 33.1 mpg and approximately normally distributed. A consumer group conducts its
own tests on a simple random sample of 15 cars of this model and finds that the mean gas mileage
for their vehicles is 31.2 mpg with a standard deviation of 3.6 mpg.
Part a : Perform a test to determine if these data support the contention that the true mean gas
mileage of this model of car is different from the published value.
10 of 11 7/20/14, 11:28 AM

Part b : Perform a test to determine if these data support the contention that the true mean gas
mileage of this model of car is less than the published value.
Part c : Explain why the answers to part a and part b are different.
a) I have placed my work and my answer on my answer sheet.
b) I want to have points deducted from my test for not working this problem.
Question 21
Your answer is CORRECT.
This is a written question, worth 14 points. DO NOT place the problem code on the answer
sheet. A proctor will fill this out after exam submission. Show all steps (work) on your
answer sheet for full credit.
Problem Code: 2123
Suppose the random variable X has pdf given by the following function with 0 ≤ x ≤ a
Part a: Find the value of a so that this is a valid pdf.
:
Part b: Find P(x ≤ 1)
a) I have placed my work and my answer on my answer sheet.
b) I want to have points deducted from my test for not working this problem.
11 of 11 7/20/14, 11:28 AM