The sample of 81 students was selected with a mean score of 90, this illustrates an example of a right tailed one sample z test.
<h3>How to illustrate the sample?</h3>
From the information given, the teacher claims that the mean score of students in his class is greater than 82 with a standard deviation of 20. In this case, the right tailed one sample z test is used.
The z value will be:
= (90 - 82)/20/✓81
= 3.6
Since 3.6 > 1.645, the null hypothesis will be rejected as there's enough evidence to support the teacher's claim.
When an online medicine shop claims that the mean delivery time for medicines is less than 120 minutes with a standard deviation of 30 minutes, the left tailed one sample test is used.
The z value will be:
= (100 - 120)/(30/✓49)
= -4.66
The null hypothesis is rejected as there is enough evidence to support the claim of the medicine shop.
Learn more about sampling on:
brainly.com/question/17831271
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