The time it takes a statistics professor to mark a student's midterm is a random variable with mean 4.6 minutes and standard deviation 1.4 minutes. If there are 80 students in the class, what is the probability the professor needs more than 371 minutes to mark all of the midterms? 0.4 0.1 0.5 0.2 0.3
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This is the mean time per midterm times the number of students, which is 4.6 minutes * 80 students = 368 minutes. Show more…
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