Question 217683: the answers are provided I just need to put in word format and do not understand it
10.29 Examine the data below showing the weights (in pounds) of randomly selected checked bags for
an airline's flights on the same day. (a) At α = .05, is the mean weight of an international bag greater?
Show the hypotheses, decision rule, and test statistic. (b) At α = .05, is the variance greater for bags on
an international flight? Show the hypotheses, decision rule, and test statistic.
Luggage
International (10 bags) Domestic (15 bags)
39 47 29 37 43
54 48 36 33 42
46 28 33 29 32
39 54 34 43 35
69 62 38 39 39
10.29 See attached output from Megastat
(a) H 0: μ1 ≤ μ2, H1: μ1 > μ2, df = 11 for unequal variances. x1 = 48.60, s21 = 141.38, x2 = 36.13, s22 =
20.981, t = 3.163, p‐value = .0045, so reject H0 at α = .05. International bags are heavier.
(b) H 0: σ12 ≤ σ22, H1: σ22 > σ22, df1 = 11, df2 = 14. For two‐tailed test, FR = F9,14 = 2.65, and FL =
1/F12,9 = 1/3.07 = .33. Since F = 6.74, international bags have greater variance.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 10.29 Examine the data below showing the weights (in pounds) of randomly selected checked bags for
an airline's flights on the same day. (a) At α = .05, is the mean weight of an international bag greater?
Show the hypotheses, decision rule, and test statistic. (b) At α = .05, is the variance greater for bags on
an international flight? Show the hypotheses, decision rule, and test statistic.
Luggage
International (10 bags) Domestic (15 bags)
39 47 ..................29 37 43
54 48 ..................36 33 42
46 28 ..................33 29 32
39 54 ..................34 43 35
69 62 ..................38 39 39
10.29 See attached output from Megastat
(a) Ho: μ1 ≤ μ2,
----H1: μ1 > μ2,
Comment: Above are the hypotheses for test if the international
weights are greater than the domestic bag weights.
---------------------
df = 11 for unequal variances.
Comment: Megastant uses its own formula for determining the degrees of
freedom.
---------------------
x1 = 48.60, s21 = 141.38,
x2 = 36.13, s22 = 20.981,
Comment: Above are the sample means and the sample standard deviations
for the two sets of data.
---------------------
t = 3.163, p‐value = .0045,
Comment: t is the test statistic and corresponding p-value
----------------------
so reject H0 at α = .05. International bags are heavier.
Comment: Since the p-value is less than 5%, you reject Ho.
You they conclude that H1 is correct.
-----------------------------------------------------------------
(b) Ho: σ12 ≤ σ22,
----H1: σ22 > σ22,
Comment: Hypoteses for testing variances.
-------------------------------------------------
df1 = 11, df2 = 14.
Comment: degrees of freedom
-------------------------------------------------
For two‐tailed test, FR = F9,14 = 2.65, and FL = 1/F12,9 = 1/3.07 = .33.
Comment: It is a 2-tail test so you have a right(FR) and a left(FL)
critical value to consider.
-----------------------------------
Since F = 6.74, international bags have greater variance.
Comment: Megastant finds that the test statistic is F=6.74
which is to the right of 2.65 so you reject Ho and accept
H1.
------------------
Cheers,
Stan H.
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