Do cars get better gas mileage on the highway? The table shows the mileage per gallon of cars on city streets and the mileage per gallon of cars on the highway. Assume that the two samples are randomly selected. At the 0.1 significance level, test the claim that the mean difference in miles per gallon is higher for cars on the city streets. (Be sure to subtract in the same direction).
Do cars get better gas mileage on the highway?
The table shows the mileage per gallon of cars on city streets and the mileage per gallon of cars on the highway. Assume that the two samples are randomly selected. At the 0.1 significance level, test the claim that the
(Be sure to subtract in the same direction).

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Test Statistic =
(Round to three decimal places.)
Critical value(s) =
(Round to three decimal places.)
p-value =
(Round to four decimal places.)
Shade the sampling distribution curve with the correct critical value(s) and shade the critical regions. The
arrows can only be dragged to t-scores that are accurate to 1 place after the decimal point (these values
correspond to the tick marks on the horizontal axis). Select from the drop down menu to shade to the left,
to the right, between or left and right of the t-score(s).
Shade: Left of a value
Click and drag the arrows to adjust the values.
-4
-2
-1
2
3
4
-1,5
Decision: Select an answer
Conclusion: Select an answer
v the claim that the mean difference in
miles per gallon is higher for cars on the city streets."
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Given that,
Sample size
The difference between two paired samples is calculated using formula as follows:
City |
Highway |
Difference (d) |
27.7 | 31.9 | -4.20 |
17.6 | 16.5 | 1.10 |
18.8 | 27.5 | -8.70 |
28.2 | 34.6 | -6.40 |
21.3 | 26.4 | -5.10 |
19.1 | 30.4 | -11.3 |
28.3 | 26.7 | 2.00 |
20 | 24.1 | -4.10 |
Mean and standard deviation of difference is calculated using EXCEL functions as given below:
Mean: “=AVERAGE (select array of data values)”
Standard deviation: “=STDEV (select array of data values)”
The mean of the difference is
Standard deviation of difference
Hypothesis:
(That is, the mean difference in miles per gallon is not higher for cars on the city streets.)
(That is, the mean difference in miles per gallon is higher for cars on the city streets.)
Degrees of freedom is
Test Statistic:
The test statistic value can be obtained as follows:
Step by step
Solved in 3 steps with 3 images
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