Question 468313
a) z=(91-73)/6=18/6=3
.9987  the probability that a student scored below 91 on exam.
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b) z=(60-73)/6=-13/6=-2.1667
z=(80-73)/6=13/6=2.1667
.9697  the probability that a student scored between 60-80 on the exam.
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c) 1.6949=(x-73)/6
x-73=10.1694
x=83.2
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d) z=(64-60)/3=4/3=1.3333
z=(80-73)/6=13/6=2.1667
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Ed