# Probability Theory: Probability Types and Assumptions

Discuss the three types of probability and the three assumptions underlying the probability theory.

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1. Discuss the three types of probability and the three assumptions underlying the probability theory.

There are types and approaches to probability, and some authors refer to both as types, so I will provide both the three types and three approaches for you to consider based on your course content.

A. Three types of probabilities are as follows:

1). Marginal Probability:

A marginal probability is usually calculated by dividing some subtotal by the whole. For example, the probability of a person wearing glasses is calculated by dividing the number of people wearing glasses by the total number of people. Marginal probability is denoted P(X), where X is some event.

2). Union Probability:

A union probability is denoted by P(X or Y), where X and Y are two events. P(X or Y) is the probability that X will occur or that Y will occur or that both X and Y will occur. The probability of a person wearing glasses or having blond hair is an example of union probability. All people wearing glasses are included in the union, along with all blondes and ...

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This solution discusses the three types of probability and the three assumptions underlying the probability theory.