The binomial distribution arises from counting the number of heads in a prespecified number of tosses, or trials . This is a model for the way that data is produced for a vast number of examples in statistics. In particular, we will use this model when examining the proportion of a random sample that belongs to a particular category.
Combinations are the way to count the number of ways that x things can be chosen from n.
These are needed to determine the probability that a binomial random variable takes on a particular value. Probabilities for binomial random variables can be determined by formula or by using a table in the back of the book. You should know both. Every binomial random variable is described by two numbers, or parameters . Here is a list of all the possible sequences of outcomes.