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Part III: Distributions and the Central Limit Theorem
Normal distribution, mean = 90, standard deviation = 30
150
30
a
Normal distribution, mean = 120, standard deviation = 30

0 0 30 60 90 120 150 180 210 240
60
180
210
240
90
120
b
Figure 9-1: Normal distribution, mean = 90, standard deviation = 10
Three
normal
distribu-
tions, with
means and
standard
deviations
of a) 90 and
30; b) 120
and 30; and
c) 90 and 10,
respectively. 0 30 60 90 120 150 180 210 240
c

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