Probability of Independent and Dependent Events

Clara picks a marble at random, puts it back, and then picks another marble at random.

• Dependent
• Independent

Pablo chooses a colored marble from a mixed bag and writes down the color. Pablo leaves it out and then draws another.

• Independent
• Dependent

The outcome of one event does NOT influence the outcome of the other event

• independent event

• tree diagram

• simple event

• odds

The outcome of one event DOES influence the outcome of the other event

• mutually exclusive event

• probability

• dependent event

• simple probability

How do you find compound probability?

• Multiply your probabilities
• Add your probabilities
• Divide your probabilities
• Subtract your probabilities

Is the event INDEPENDENT or DEPENDENT?
Amy plays card games.  She picks a card at random.  Then without putting the first card back, he picks a second card at random.

• Independent
• Dependent

Is the event INDEPENDENT or DEPENDENT?
The spinner is spun twice.  What is the probability that it lands on red first and then blue?

• Independent
• Dependent

What is the formula to be used in finding the probability of independent events?

• $P\left(A\cap B\right)=P\left(A\right)\cdot P\left(B\right)$

• $P\left(A\cup B\right)=P\left(A\right)\cdot P\left(B\right)$

• $P\left(A\cap B\right)=P\left(A\right)+P\left(B\right)$

• $P\left(A\cup B\right)=P\left(A\right)+P\left(B\right)$

What is the formula to be used in finding the probability of the events that are dependent?

• $P\left(A\cap B\right)=P\left(A\right)\cdot P\left(B\right)$

• $P\left(A\cup B\right)=P\left(A\right)\cdot P\left(B\right)$

• $P\left(A\cap B\right)=P\left(A\right)\cdot P\left(B\ after\ A\right)$

• $P\left(A\cup B\right)=P\left(A\right)+P\left(B\ after\ A\right)$

What is the probability of tossing a coin four times and getting tails each time?

• 1/16
• 1/8
• 1/2
• 1/4