Discrete Probability & Expected Values

Probability is a measure of the likelihood that an event will occur, expressed as a number between 0 (impossible event) and 1 (certain event).

A probability of 0 means that the event is impossible and cannot occur.

A probability of 1 means that the event is certain to occur.

The expected value is the average outcome of a random variable, calculated as the sum of all possible values, each multiplied by its probability.

To calculate the expected value, multiply each possible outcome by its probability and sum all these products.

The probability of an event that is as likely to happen as not is 0.5.

The probability of landing on any one section is 1/6.

The probability of an event that is certain to happen is 1.

Expected number = (Probability of 1 child * 1) + (Probability of 2 children * 2) + (Probability of 3 children * 3).

An unlikely event has a probability greater than 0 but less than 0.5.