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If you make random guesses for a multiple-choice test with 8 questions a. Would it be unlikely to be wrong on all your guesses? Why or why not? b. What is the probability you get at least one answer correct?

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Final answer:

The probability of getting all answers wrong on a multiple-choice test with 8 questions is approximately 0.0175, while the probability of getting at least one answer correct is 0.9825, or 98.25%.

Step-by-step explanation:

To calculate the probability of getting a question wrong on a multiple-choice test with 8 questions, we need to consider that each question has 3 possible choices. Therefore, the probability of guessing a question correctly is 1/3, and the probability of guessing a question wrong is 2/3. So, the probability of getting all 8 questions wrong is (2/3)^8, which is approximately 0.0175.

The probability of getting at least one answer correct can be calculated as the complement of getting all 8 questions wrong. So, the probability of getting at least one answer correct is 1 - 0.0175 = 0.9825, or 98.25%.

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