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Chapter 6
Modeling Solutions
e secret to lm is that it is an illusion.
GEORGE LUCAS
Life is full of models. Perhaps in your childhood you made plastic models
of cars or boats. Models are also used to show o new clothing designs.
Economists create models of nancial systems, and sociologists model
populations.
A model is nothing more than a replica or representation of some object
or system. Sometimes models are used to capture things too small, too
fast, or too distant to be understood in other ways. A toy model of the
planets of our solar system and a chemist’s three-dimensional model of
molecular structures are useful because they hel