1. A set of final examination grades in an introductory statistics course is normally distributed with a mean of 73 and a standard deviation of 8. a) What is the probability of getting a grade of 91 or less on this exam? b) What is the probability that a student scored between 62 and 80? c) If the professor gives a student grade B on a score of 75 on this exam or a grade B on score of 68 on a different exam where the mean is 62 and the standard deviation is 4? Show your answer statistically [that is do the calculation] and explain in which exam the student has a higher probability to get grade B
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Given that the mean (μ) is 73 and the standard deviation (σ) is 8, we need to find P(X ≤ 9). Z = (9 - 73) / 8 = -8 From the Z-table, the probability of Z being less than -8 is very close to 0. Therefore, the probability of getting a grade of 9 or less on the exam Show more…
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