Imagine that you are taking a very difficult test (in a statistics class of course), historically...

Imagine that you are taking a very difficult test (in a statistics class of course), historically the mean grade is 43.5 out of 100 with a standard deviation of 15.2. Treating the historical average and standard deviation as parameters of a normal curve:

A.) What is the probability of passing with a score of 60 or higher.

B.) What is the probability of getting an A- (90 to 92.5)

C.) If a new class of 35 students takes the test, how many students in the new class would you expect to get a B (80 to 89) ?

D.) Given your results assume that we actually gave such a test to 10 sections (of ten students each) and discovered that the average number of students getting an A on the exam in each section was 7. Using your knowledge of probability what can you suggest about this situation ?

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Answer

a) 0.13884

b) 0.0005

c) None of the students

d) Not possible

orchestra answered 1 year ago

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