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MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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
Transcribed Image Text:The professor of a introductory calculus class has stated that, historically, the distribution of final exam grades in the course resemble a
Normal distribution with a mean final exam mark of u = 61% and a standard deviation of g = 10%.
If using/finding z-values, use three decimals.
(a) What is the probability that a random chosen final exam mark in this course will be at least 71%? Answer to four decimals.
(b) In order to pass this course, a student must have a final exam mark of at least 50%. What proportion of students will not pass the calculus
final exam? Use four decimals in your answer.
(c) The top 4% of students writing the final exam will receive a letter grade of at least an A in the course. To two decimal places, find the
minimum final exam mark needed on the calculus final to earn a letter grade of at least an A in the course.
%
(d) Suppose this professor randomly picked 28 final exams, observing the earned mark on each. What is the probability that 7 of these have
a final exam grade of less than 50%? Use four decimals in your answer.
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