Using the t-distribution, it is found that the test statistic for the hypotheses test is given by:
At the null hypotheses, it i tested if the mean difference remains the same, that is:
At the alternative hypotheses, it is tested if it has decreased, hence:
.
The test statistic is given by:
The parameters are:
is the sample mean.
is the value tested at the null hypothesis.
- s is the standard deviation of the sample.
- n is the sample size.
The parameters are given as follows:
.
Hence the test statistic is given by:
More can be learned about the t-distribution at brainly.com/question/16162795
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