It is thirteen because you have to add to 6 till you get eleven and you go up 8 more and then you subtract it all and get your answer
The decision when the z value is within the rejection region is that we'll have to reject the null hypothesis.
<h3>What is a rejection region?</h3>
It should be noted that the rejection region is also known as the critical region. It is the set of values where the null hypothesis is rejected.
When the observed test statistic is in the rejection region, we'll have to reject the null hypothesis and then accept rte alternative hypothesis.
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