1. PROBABILITY Probability is represented as a ratio of the number of ways an event actually occurs compared to the number of possible outcomes

2. PROBABILITY Probability is represented as a ratio of the number of ways an event actually occurs compared to the number of possible outcomes For example, let’s look at a dice rolled one time.

3. PROBABILITY Probability is represented as a ratio of the number of ways an event actually occurs compared to the number of possible outcomes For example, let’s look at a dice rolled one time. What is the probability of rolling a two ?

4. PROBABILITY Probability is represented as a ratio of the number of ways an event actually occurs compared to the number of possible outcomes For example, let’s look at a dice rolled one time. What is the probability of rolling a two ? A two occurs one time on a die… There are six possible numbers we can roll…

5. PROBABILITY

6. EXAMPLE # 2 : What is the probability of drawing an ace in a deck of cards ?

7. PROBABILITY EXAMPLE # 2 : What is the probability of drawing an ace in a deck of cards ? There are 4 aces in a deck of cards… There are 52 cards in a deck…

8. PROBABILITY

12. Compound events… if I draw one card from a deck of cards and then draw ANOTHER card, that is a compound event. We are attempting the trial more than one time.

13. PROBABILITY Compound events… if I draw one card from a deck of cards and then draw ANOTHER card, that is a compound event. We are attempting the trial more than one time. There are two types : With replacement – you replace the card or gumball, etc. for the next trial

14. PROBABILITY Compound events… if I draw one card from a deck of cards and then draw ANOTHER card, that is a compound event. We are attempting the trial more than one time. There are two types : With replacement – you replace the card or gumball, etc. for the next trial Without replacement – you DO NOT replace the item after the first trial

15. PROBABILITY Compound events… if I draw one card from a deck of cards and then draw ANOTHER card, that is a compound event. We are attempting the trial more than one time. There are two types : With replacement – you replace the card or gumball, etc. for the next trial Without replacement – you DO NOT replace the item after the first trial To calculate the probability, you multiply the ratios…

16. PROBABILITY Compound events… if I draw one card from a deck of cards and then draw ANOTHER card, that is a compound event. We are attempting the trial more than one time. There are two types : With replacement – you replace the card or gumball, etc. for the next trial Without replacement – you DO NOT replace the item after the first trial To calculate the probability, you multiply the ratios… EXAMPLE : A bag has 3 red chips and 5 blue chips. What is the probability of drawing a red chip on the first try and a blue chip on the second try with replacement ?

17. PROBABILITY

19. Compound events… if I draw one card from a deck of cards and then draw ANOTHER card, that is a compound event. We are attempting the trial more than one time. EXAMPLE : A bag has 3 red chips and 5 blue chips. What is the probability of drawing a red chip on the first try and a blue chip on the second try WITHOUT replacement ?

20. PROBABILITY Notice how the number of possible outcomes changed because we didn’t replace the red chip after the first trial…

21. PROBABILITY