Test whether the population
Suggest the preferable system.
Answer to Problem 38SE
There is sufficient evidence to conclude that, there is a difference between the population mean checkout times of the two systems.
The preferable system is system A.
Explanation of Solution
Calculation:
The results of the tests on customer checkout times at system A and system B are as follows:
System A | System B |
The level of significance is
State the hypotheses.
The test hypotheses are as follows:
Null hypothesis:
That is, there is no difference between the population mean checkout times of the two systems.
Alternative hypothesis:
That is, there is a difference between the population mean checkout times of the two systems.
Test statistic:
The test statistic for hypothesis tests about
Substitute
Thus, the test statistic is 2.79.
Software procedure:
Step-by-step procedure to obtain the probability value using Excel:
- Open an EXCEL sheet and select the cell A1.
- Enter the formula =NORM.S.DIST(2.79,TRUE) in the cell A1.
- Press Enter.
Output obtained using EXCEL software is given below:
From the output, the p-value for the left tail is 0.997365.
For a two-tailed test, the p-value is two times of upper-tail area.
From the output:
Thus, the p-value is 0.0052.
Rejection rule:
If
If
Conclusion:
Here, the p-value is less than the level of significance.
That is,
From the rejection rule, the null hypothesis is rejected.
Therefore, there is sufficient evidence to conclude that, there is a difference between the population mean checkout times of the two systems.
Thus, there is a difference between the population mean checkout times of the two systems.
Here, the mean checkout time of system B is less when compared to the mean checkout time of system A.
Therefore, system A is preferable.
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Chapter 10 Solutions
Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card) (MindTap Course List)
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt