Complete Question
The complete question is shown on the first uploaded image
Answer:
a
C
b
C
c
C
d
A
Step-by-step explanation:
From the question we are told that
The population mean is
Generally the Null hypothesis is
The Alternative hypothesis is
Considering the parameter given for part a
The sample size is n = 15
The test statistics is t = 1.66
The level of significance
The degree of freedom is evaluated as
Using the critical value calculator at (social science statistics web site )
We are making use of this because it is a one-tail test
Looking at the value of t and the we see that
so the null hypothesis would not be rejected
Considering the parameter given for part b
The sample size is n = 15
The test statistics is t = -1.66
The level of significance
The degree of freedom is evaluated as
Using the critical value calculator at (social science statistics web site )
Looking at the value of t and the we see that t does not lie in the area covered by
(i.e the area from -2.145 downwards on the normal distribution curve ) hence we fail to reject the null hypothesis
Considering the parameter given for part c
The sample size is n = 26
The test statistics is t = -2.55
The level of significance
The degree of freedom is evaluated as
Using the critical value calculator at (social science statistics web site )
Looking at the value of t and the we see that t does not lie in the area covered by
(i.e the area from -2.787 downwards on the normal distribution curve ) hence we fail to reject the null hypothesis
Considering the parameter given for part d
The sample size is n = 26
The test statistics is t = -3.95
The level of significance
The degree of freedom is evaluated as
Using the critical value calculator at (social science statistics web site )
Looking at the value of t and the we see that t lies in the area covered by
(i.e the area from -2.787 downwards on the normal distribution curve ) hence we reject the null hypothesis
