# chapter 9

## 24 terms

### certain

sure to happen having a probability

### combination

an arrangement of items or events in which order does not matter

### dependent events

Events for which the outcome of one event affects the probability of the other

### equally likely outcomes

outcomes that have the same probability

### event

an outcome or set of outcomes of an experiment or situation

### experiment

In probability any activity based on chance (such as tossing a coin)

### experimental probability

the ratio of the number of times an event occurs to the total number of trials or times that the activity is performed

### factorial

the product of all whole number breaks down into its prime factors

### fair

when all outcomes of an experiment are equally likely,the experiment is said to be fair

### Fundamental Counting Principle

If one event has m possible outcomes and a second event has n possible outcome after the first event has occurred, then there are m x n total possible outcome for the two events

### impossible

can never happen; having a probability of 0

### independent events

events for which the numerator is greater than or equal to the denominator.

### mutually exclusive

two events are mutually exclusive if they cannot occur in the same trial of an experiment

### odds against

the ratio of the number of unfavorable outcomes to the number of favorable outcomes

### odds in favor

the ratio of the number of favorable outcomes to the number of unfavorable outcomes

### outcome

a possible result of a probability experiment

### permutation

An arrangement of items or events in which order is important.

### probability

a number from 0 to 1 (or 0% to 100%) that describes how likely an event is to occur.

### random numbers

In a set of random numbers, each number has an equal chance of being selected

### sample space

all possible outcomes of an experiment

### simulation

a model of an experiment, often one that would be too difficult or too time consuming to actually perform

### theoretical probability

the ratio of the number of equally outcomes in an event to the total number of possible outcomes

### tree diagram

a branching diagram that shows all possible combinations or outcomes of an event

### trial

In probability, a single repetition or observation of an experiment