In: Statistics and Probability
A pet association claims that the mean annual cost of food for dogs and cats are the same. The results for samples for the two types of pets are shown below. At
alphaαequals=0.05
can you reject the pet association's claim? Assume the population variances are not equal. Assume the samples are random and independent, and the populations are normally distributed. Complete parts (a) through (e) below.
Dogs |
Cats |
|||||||
---|---|---|---|---|---|---|---|---|
|
|
|||||||
|
|
|||||||
|
|
(a) Identify the claim and state
Upper H0
and
Upper H Subscript aHa.
Which is the correct claim below?
A.
"The mean annual cost of food for cats is greater than the cost for dogs."
B.
"The mean annual cost of food for dogs is greater than the cost for cats."
C.
"The mean annual costs of food for dogs and cats are equal."
D.
"The mean annual costs of food for dogs and cats are not equal."
What are
Upper H0
and
Upper H Subscript aHa?
The null hypothesis,
Upper H0,
is
(1)
The alternative hypothesis,
Upper H Subscript aHa,
is
(2)
Which hypothesis is the claim?
The alternative hypothesis, Upper H Subscript aHa
The null hypothesis, Upper H0
(b) Find the critical value(s) and identify the rejection region(s).
Enter the critical value(s) below.
nothing
(Type an integer or decimal rounded to three decimal places as needed. Use a comma to separate answers as needed.)
Select the correct rejection region(s) below.
A.
t greater than t 0t>t0
B.
negative t 0 less than t less than t 0−t0<t<t0
C.
t less than minus t 0 comma t greater than t 0t<−t0, t>t0
D.
t less than minus t 0t<−t0
(c) Find the standardized test statistic.
tequals=_________
(Type an integer or decimal rounded to three decimal places as needed.)
(d) Decide whether to reject or fail to reject the null hypothesis.
(3)
the null hypothesis.
(e) Interpret the decision in the context of the original claim.
At the
five percent
significance level,
(4)
enough evidence to reject the claim that the mean annual costs of food for dogs and cats are the same.
Which of the options below is correct?
(1)
mu 1 equals mu 2 .μ1=μ2.
mu 1 less than or equals mu 2 .μ1≤μ2.
mu 1 greater than or equals mu 2 .μ1≥μ2.
(2)
mu 1 not equals mu 2 .μ1≠μ2.
mu 1 greater than mu 2 .μ1>μ2.
mu 1 less than mu 2 .μ1<μ2.
(3)
Fail to reject
Reject
(4)
there is not
there is