In: Statistics and Probability
The mean area of homes in a certain city built in 2009 was 2438
square feet. Assume that a simple random sample of 11 homes in the
same city built in 2010 had a mean area of 2,297 square feet, with
a standard deviation of 225 square feet. An insurance company wants
to know if the mean area of homes built in 2010 is less than that
of homes built in 2009. Compute the P-value of the
test.
Write down your P-value. You will need it for the next
question.
Write only a number as your answer. Round to four decimal places
(for example: 0.3841).
In the last question, an insurance company wants to know if the mean area of homes built in 2010 is less than that of homes built in 2009. What is the conclusion at the 0.05 level of significance?
Question 13 options:
There is evidence to conclude that the mean area of homes built in 2010 is less than that of homes built in 2009 |
|
There is not enough evidence to conclude that the mean area of homes built in 2010 is less than that of homes built in 2009 |
|
There is evidence to conclude that the mean area of homes built in 2010 is not less than that of homes built in 2009 |
|
There is not enough evidence to conclude that the mean area of homes built in 2010 is not less than that of homes built in 2009 |
H0: = 2438
Ha: < 2438
Test statistics
t = - / S / sqrt(n)
= 2297 - 2438 / 225 / sqrt(11)
= -2.08
This is test statistics value.
Using T table,
p-value for one tailed test with t = 2.08 and df = 10
p-value = 0.0321
Conclusion -
Since p-value < 0.05, we have sufficient evidence to reject H0.
We conclude that ,
There is evidence to conclude that the mean are of the homes build in 2010 is less than that of homes
build in 2009.