A sample of 30 observations is selected from a normal population. The sample mea
ID: 3132092 • Letter: A
Question
A sample of 30 observations is selected from a normal population. The sample mean is 21, and the population standard deviation is 6. Conduct the following test of hypothesis using the 0.05 significance level. H_0 : mu 20 Is this a one- or two-tailed test? "One-tailed"-the alternate hypothesis is greater than direction. "Two-tailed"-the alternate hypothesis is different from direction. What is the decision rule? (Round your answer to 3 decimal places.) What is the value of the test statistic? (Round your answer to 2 decimal places.) What is your decision regarding H_0? Reject Do not reject There is evidence to conclude that the population mean is greater than 20. What is the p-value? (Round your answer to 4 decimal places.)Explanation / Answer
A)
Formulating the null and alternative hypotheses,
Ho: u <= 20
Ha: u > 20
As we can see, this is a right tailed test.
Hence, it is a ONE TAILED TEST. [ANSWER]
****************************
b)
Thus, getting the critical z, as alpha = 0.05 ,
alpha = 0.05
zcrit = + 1.644853627
Hence,
REJECT HO when z > 1.645. [ANSWER]
******************************
c)
Getting the test statistic, as
X = sample mean = 21
uo = hypothesized mean = 20
n = sample size = 30
s = standard deviation = 6
Thus, z = (X - uo) * sqrt(n) / s = 0.912870929 = 0.91 [ANSWER]
******************************
d)
As z < 1.645, we DO NO REJECT HO. [ANSWER]
*****************************
e)
Also, the p value is
p = 0.180655214 [ANSWER]
******************************
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.