In: Statistics and Probability
2.) The Kellogg Company periodically compares sales across departments. In one particular instance, they would like to determine if sales of snacks are different from sales of frozen foods. If snacks are group 1 and frozen foods are group 2, what are the hypotheses for this test?
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Here we have given that
Claim: To check weather the sales of snacks group-1 are different from sales of frozen foods group-2.
The hypothesis is
v/s
That is here option C is Correct
Now, we have given that
n1=1st sample size group 1= 19
=1st sample mean group 1 =64.761
S1=1st sample standard deviation group1 =10.6264
n2 =2nd sample size group 2=25
= 2nd sample mean group 2=64.728
S2=2nd sample standard deviation group 2=13.241
Here we assume the two population variances are equal
We can find the test statistics
Now,
We find the test statistics for two sample t test
Test statistics is:
Where =pooled sample variance
Now we find it
=106.84
Now we get test statistics is
= 0.009 0.01
here we get the
Test statistics is 0.009
Now we find the p-value
=level of significance=0.05
Degrees of freedom = n1+n2-2 = 19+25-2 =42
This is two tailed test
we get
P-value= 0.9929 using EXCEL =TDIST(TSTAT=0.009 , D.F=42,TAIL=2)
We get
P-value=0.9929
That is here option D (4) is correct
Decision:
P-value > 0.05
That is we fail to reject Ho Null hypothesis
conclusion:
That is we say that there is no sufficient evidence that the sales of snacks group-1 are different from sales of frozen foods group-2.