Probability and Odds

1
Probability and Odds

• Weather ?
• or Lottery Ticket ?

2
Probability favorable outcomes
total possible outcomes
3
Probability and Weather

• The weatherperson says there is a 70 chance of
  rain this afternoon. What is the probability it
  will not rain?

4
Probability and Dice
You roll a die once. What is the probability
P(4)
P(even )
5
Probability and Dice
You roll two dice. What is the probability
P(two 4s)
P(both even )
6
Probability and Cards

• You pick one card from a standard 52 card deck.
  What is the probability of picking a Jack?

7
Probability and Cards

• You pick one card from a standard 52 card deck.
  What is the probability of picking a black card?

8
Probability and Cards

• You pick two cards from a standard 52 card deck.
  What is the probability of picking 2 black cards?

9
Probability and Cards

• What is the probability of being dealt 3 kings in
  a hand of 5 card stud poker?

10
Probability favorable outcomes
total possible outcomes

• Odds
• successes failures

11
Probability and Weather

• The weatherperson says there is a 70 chance of
  rain this afternoon. What are the odds it will
  rain?

12
Probability and Weather

• The weatherperson says there is a 70 chance of
  rain this afternoon. What are the odds it will
  NOT rain?

13
Probability of Multiple Events

• Overview
• And ? Multiply
• Or ? Add

14
Probability of Multiple Events

• If A and B are Independent Events
• P(A and B) P(A) P(B)

If A and B are Dependent Events P(A and B)
P(A) P(B after A)
15
Probability of Multiple Events

• Two students are selected at random from this
  class to be given two different prizes. What is
  the probability of selecting two girls?

16
Probability of Events involving Or

• P(A or B) P(A) P(B)
• if A and B are Mutually Exclusive Events.

P(A or B) P(A) P(B) P(A and B) if A and B
are Inclusive Events.
17
Probability of Events involving Or

• Find the probability of drawing a 9 or a face
  card when picking one card from a standard 52
  card deck.

18
Probability of Events involving Or

• Find the probability of drawing a Queen or a
  heart when picking one card from a standard 52
  card deck.

19
Probability of Events involving Or

• One student is to be picked at random from this
  class to win the Big Deal of the Day. Find
  the probability the student is a girl or a
  blonde.