Page 9 - Probability Demystified

PREFACE

‘‘The probable is what usually happens.’’ — Aristotle

Probability can be called the mathematics of chance. The theory of probabil-
ity is unusual in the sense that we cannot predict with certainty the individual
outcome of a chance process such as flipping a coin or rolling a die (singular
for dice), but we can assign a number that corresponds to the probability of
getting a particular outcome. For example, the probability of getting a head
when a coin is tossed is 1/2 and the probability of getting a two when a single
fair die is rolled is 1/6.
We can also predict with a certain amount of accuracy that when a coin is
tossed a large number of times, the ratio of the number of heads to the total
number of times the coin is tossed will be close to 1/2.
Probability theory is, of course, used in gambling. Actually, mathemati-
cians began studying probability as a means to answer questions about
gambling games. Besides gambling, probability theory is used in many other
areas such as insurance, investing, weather forecasting, genetics, and medicine,
and in everyday life.
What is this book about?
First let me tell you what this book is not about:

. This book is not a rigorous theoretical deductive mathematical
approach to the concepts of probability.
. This book is not a book on how to gamble.
And most important

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