HP 39gs Instruction Manual page 2

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HP 39gs Inference and Hypothesis Testing
Are there really 50 matches per box? I
A company makes boxes of matches which are supposed to contain an average of 50 matches. A student has counted the contents
of 20 boxes and found the results below. Using a 5% confidence level, decide whether the company's claim is correct.
Begin by entering the data into the Statistics aplet. The values of the mean and standard deviation will be transferred from here to
the Inference aplet.
Matches per box
47, 50, 52, 51, 53, 51,
49, 49, 52, 53, 54, 48,
53, 55, 52, 54, 54, 53,
48, 48
Change to the Inference aplet and choose the test and the alternate hypothesis. In this case we are working with a single sample
and we do not know the standard deviation of the underlying population, so we will use the Student-t test and choose the alternate
hypothesis that the mean of the real underlying population from which the sample was drawn is not equal to that of the proposed
population.
Change now to the NUM SETUP view to enter the required values for analysis. Rather than entering them by hand, press the
IMPORT key. If you have more than one copy of the Statistics aplet (under other names), as in the case shown below, then you will
be presented with a list of aplets from which to choose.
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HP 39gs Inference and Hypothesis Testing
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