1. Probability and Sample Space

2. Probability Probability is the chance that something has of occurring.
Probability exists on a continuum…
…just like black and white
Shades of gray!
What lies in the middle?

3. Probability Probability is exactly like that:
Probability is expressed as a fraction, and can be anything from P = 0 to P = 1
In between a probability of 0 and a probability of 1, there are an infinite number of probabilities that are possible
P = 0
P = 1

4. Probability
P = 0
P = 1
Impossible Event
Certain Event
In general, events are given a likelihood of happening, based on their probability
A probability of 0 means that there is no way the event will occur, or it is impossible
A probability of 1 means that the event will always happen, or it is certain

5. Probability
P = 0
P = 1
P =
Impossible Event
Certain Event
A probability of means that the event is equally likely and unlikely, like a coin being flipped and landing on heads
A probability of means that it is unlikely to occur
A probability of means that it is likely to occur

6. Probability What is an event that is impossible?
Choosing an E out of the letters in the word BOOKBAG
Picking a red tile out of a bag containing only blue and green tiles

7. Probability What is an event that is certain?
Choosing a boy or a girl out of the kids in my fifth period class
Choosing a B, O, or K out of the letters in the word BOOK
Picking a red tile out of a bag containing only red tiles

8. Probability Outcome: A possible result to an event/trial Event:
A collection of outcomes
Favorable Outcome:
The outcome you want to have
Unfavorable Outcome:
Any outcome you do not want to have

9. Probability Finding probability: p = Remember:
favorable outcomes are the things you want to happen
total outcomes are all the possibilities that could happen
Number of favorable outcomes
Total number of outcomes

10. Probability
Find the probability of rolling a number cube, and getting a 3
P =

11. Probability
Find the probability of rolling a number cube, and getting an odd #
P =

12. Probability
Use the pictures below to answer the following:
What is the probability of choosing a quarter with a person on it?
What is the probability of choosing a quarter with the outline of a state on it?
What is the probability of choosing a quarter with a horse? With no horse?

13. Sample Spaces

14. Sample Space
A Sample Space is a list of all the possible ways an event(s) can occur.
Imagine that you are going to Brusters to get an ice cream cone.
Brusters offers three types of cones:
Waffle, Sugar, and Cake (plain)
They offer three basic flavors of ice cream:
Chocolate, Vanilla, and Strawberry

15. Sample Space Ice Cream Cones
Let’s make a sample space table:
Waffle (W)
Sugar (S)
Cake (C)
Choc. (c) Wc Sc Cc
Van (v) Wv Sv Cv
Straw (s) Ws Ss Cs

16. Sample Space Flipping a Coin Twice
Heads (H)
Tails (T)
Heads (h) Hh Th
Tails (t) Ht Tt