# Probability

“The probable is what usually happens.”    Aristotle

The probability of an event is a measure of the likelihood that the event will occur.
The probability of any event can range from 0 to 1.

Probability of an event

Predict & Display Data

Probability – Sample Space

### PR17      Probability of picking a tile from a bag.

PR18  A Pair of Dice (Probability)

Finding the Probability of Independent Events

(Sample space UNCHANGED)

If A and B are independent events, then

P(A and B) = P(A)•P(B)

Dependent Events (Help),

Tree Diagram (Help)

Probability Voc

Statistics_Voc

Finding the Probability of Dependent Events

(Sample space DECREASES)

If A and B are dependent events, then

P(A and B) = P(A) • P(B given A)

### PR25      2Bills

PR26  School Items (Probability)

PR27  Marbles (Probability)

Probability – Counting Principle Probability – Independent Event Probability Application

Theoretical probability

Theoretical Probability is determined through reasoning (the ratio of the number of favorable outcomes to the number of possible outcomes).

Experimental probability

Experimental probability is found by repeating an experiment and observing the outcomes.

A monkey is sitting by and hitting 4 keys randomly. Suppose that the monkey is answering a multiple choice MATH STAAR TEST. There are 56 questions and each question has 4 options. Find the experimental probability

### Probability Writing

Probability_W   Probability Writing

Probability rules