a) The percentage of students who passed the exam, given that they completed the exam review is of 73%.
b) The percentage of students who passed the exam, given that they did not complete the exam review, is of 27%.
c) There is a positive association between passing the exam and completing the exam review.
<h3>How to obtain the percentages?</h3>
A percentage is obtained by the division of the desired amounts by the total amounts, multiplied by 100%.
For item a, these amounts are given as follows:
- Desired: 55% that passed and completed the exam review.
Hence the percentage is of:
p = 55/75 = 0.73 = 73%.
For item b, these amounts are given as follows:
- Desired: 20% that passed and did not completed the exam review.
Hence the percentage is of:
p = 20/75 = 0.27 = 27%.
There is a positive association between passing the exam and completing the exam review, as the percentage of students who passed completing the review, found in item a, is greater than the percentage of students who passed without completing the review, found in item b.
More can be learned about percentages at brainly.com/question/843074
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