Question 335773: It was reported that a certain population had a mean of 27. To test this claim, you selected a random sample of size 100. The computed sample mean and sample standard deviation were 25 and 7, respectively. At the 0.05 level of significance, you can claim that the average of this population is:
a. not equal to 25.
b. equal to 25.
c. not equal to 27.
d. equal to 27.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! It was reported that a certain population had a mean of 27. To test this claim, you selected a random sample of size 100. The computed sample mean and sample standard deviation were 25 and 7, respectively. At the 0.05 level of significance, you can claim that the average of this population is:
a. not equal to 25.
b. equal to 25.
c. not equal to 27.
d. equal to 27
-------------------------
----
t(25) = (25-27)/[7/sqrt(100)] = -2.8571
------
The critical values are +-invT(0.025 with df= 99) = -1.9842
----
Since the test stat is in the reject interval, reject Ho.
Ans: a
======================
Cheers,
stan H.
|
|
|
