SOLUTION: A set of mid term examination grades in an undergraduate introductory statistics course at a large public university (i.e., there were lots of students) was found to be normally di

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Question 508575: A set of mid term examination grades in an undergraduate introductory statistics course at a large public university (i.e., there were lots of students) was found to be normally distributed with a mean of 73 and a standard deviation of 8.
1. What is the probability of getting between a 60 and 70 on this exam?
Answer by stanbon(75887) (Show Source):
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normally distributed with a mean of 73 and a standard deviation of 8.
1. What is the probability of getting between a 60 and 70 on this exam?
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z(60) = (60-73)/8 = -13/8 = -1.6250
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z(70) = (70-73)/8 = -3/8 = -0.375
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Using my TI-84 I get:
P(60< x <70) = P(-1.625< z <-0.375)
= normalcdf(-1.625,-0.375)
= 0.3017
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Cheers,
Stan H.
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