Search

# Probability Examples

### Common Core Standard: HSS.CP.A.1

What is probability? In simple terms it is how ” likely” an event will occur. For instance, if you flip a coin how likely is it you will flip a heads? In order to calculate probability follow these steps.

# Probability of Independent Events

Independent Events:  Events are independent if the result of the second event is not affected by the actions of the first event.

You may think of independent events as isolated events.

For example: Flipping a coin. Each flip of the coin has no impact on the next flip.

If you have three red marbles, and three blue marbles placed on a table. What are the chances of picking a blue marble, and then a red marble if the marbles are replaced each time? Because the marbles are replaced each time they have no bearing on the next event.

Independent events involving “and”
When you have independent events along with the statement “and” use the formula

P(A and B) = P(A) x P(B)

Please note P( ) means the probability of an event. The event is placed in the ( ) for example

What is the probability of rolling a 5 on a six sided die can be written P(5)