Probability theory is, of course, used in gambling or lottery but it cant HELP you to win
at gambling. Actually, mathematicians began studying probability as a means to answer
questions about gambling games but not about its winnings. Besides gambling,
probability theory is used in many other areas such as insurance, investing, weather
forecasting, genetics, and medicine, and in everyday life.
Probability can be called the mathematics of chance. The theory of probability 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 (singularfor 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.
But at the same time, it is a fact that 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. It is called the
classical version of probability, which is often used in lottery.