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Here we show some examples of binomial experiments. But before we do so, what is a binomial experiment? When an experiment satisfies the following four conditions, the experiment is called a binomial experiment. Now, we will show a couple of good examples of binomial experiments to illustrate the concept. Example #1 Consider the experiment of […]

The Poisson probability distribution is named after the French mathematician Simeon D. Poisson. Suppose there is a power outage in an apartment complex 3 times a year. You may want to find the probability that there will be exactly 2 power outage next year. This is an example of a Poisson probability distribution problem. Each […]

Suppose we are selecting a few items from a large number of distinct items and you are trying to find out how many different ways this can be done. You are trying to find the number of combinations. Suppose you want to buy 2 cars from a set of 4 distinct choices. Suppose the set […]

We define the factorial of a number as the multiplication of all integers from that number to 1. We use the symbol ! which is an exclamation mark to denote factorial and we put the exclamation mark next to a number. For example,  5!  is read as five factorial and we can evaluate 5! by multiplying […]

The standard deviation of a discrete random variable is denoted by σ and the formula to use to compute it is σ =      or  σ =     We can use the example in the previous lesson about the number of people going to the movie theater each week to look for the standard deviation. We will […]

The mean of a discrete random variable x is the average value that we would expect to get if the experiment is repeated a large number of times. The mean is denoted by μ and obtained using the formula μ = ΣxP(x) Another name for the mean of a discrete random variable is expected value. The […]

The probability distribution of a discrete random variable shows all possible values a discrete random variable can have along with their corresponding probabilities. You could use a table to organize the information. In the lesson about discrete random variable, you conducted a survey asking 200 people about the number of vehicles they own. You came […]

Before giving a definition for discrete random variable, let us define random variable. A random variable is a variable that has exactly 1 numerical value and this value is determined by the outcome of a random experiment. For example, the number of vehicles someone owns is a random variable. To find out, you will need […]