06 Probability Review.notebook
Review of Simple Probability
October 18, 2013
What is the range of values that
probability can be??
For Simple Events ­ Determine how many outcomes are possible. Ones to know...
One die = 6 outcomes
Two dice =36 outcomes
0
0.5
1
One coin = 2 outcomes
One deck of cards = 52 outcomes
Simple Probability
Continuum
"And" Compound Events
Review of Compound Probability
• 2 or more simple events combined • When the outcome of one event does not affect the outcome of a second event, these are called independent events.
with the word "and" (multiplication) • The probability of two independent events or the word "or" (add / add & subtract)
is found by multiplying the probability of • Examples: rolling a die and tossing a penny spinning a spinner and drawing a card tossing two dice tossing two coins the first event by the probability of the Compound Probability
second event. "And" Statements
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06 Probability Review.notebook
Examples
1) P(4 and C) = 2) P(<3 and E) =
3) P(odd and vowel) = October 18, 2013
"Or" Compound Events
• Events that cannot occur at the same time are called mutually exclusive.
• Suppose you want to find the probability of rolling a 2 or a 4 on a die. P(2 or 4) • Since a die cannot show both a 2 and a 4 at the same time, the events are mutually
exclusive.
4) P(<7 and a letter) = 5) P(7 and H) = "And" Examples
"Or" Statements
Example #1:
Alfred is going to the Lakeshore Animal Shelter to pick a new pet. Today, the shelter has 8 dogs, 7 cats, and 5 rabbits available for adoption. If Alfred randomly picks an animal to adopt, what is the probability that the animal would be a cat or a dog?
Why is this a "Mutually Exclusive"
example?
Since a pet cannot be both a dog and a
cat,
the cannot
events be
areboth
mutually
the
animal
a cat exclusive.
and a dog
Formula?
Example #2:
The French Club has 16 seniors, 12 juniors, 15 sophomores, and 21 freshmen as members. What is the probability that a member chosen at random is a junior or a senior? Why is this a "Mutually Exclusive"
example?
Since a person cannot be both a junior
and a senior, the event is M.E.
Formula?
"ME" Example #1
"ME" Example #2
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06 Probability Review.notebook
What is the difference between
Mutually exclusive events and
inclusive events???
Mutually Exclusive: the two events are completely
separate. Both cannot happen
at the same time.
Inclusive Events: both events COULD happen
* Middle part is added twice, but
it doesn't occur twice, so we have
to get rid of one of the overlaps!
October 18, 2013
Why subtract the "overlap" part?
Everything
Everything
in red circle
in blue
is counted
circle is
once
counted
once
Purple Area is in both circles and counted
both times, therefore it is those
probabilities have been doubled.
ME vs. Inclusive
Example:
Dec 4­9:13 PM
A 10-sided die is rolled. Find the following
probabilities.
P(5)
P(Odd)
P(Prime)
A card is chosen at random from a standard deck of cards, find the probability that the card chosen is a king or a diamond
Why is this an "Inclusive"
example?
P(5 OR Odd)
Incl.
P(Odd or Prime)
Incl.
there is a king of diamonds that can only be
counted once) This is called mutually inclusive
Formula?
P(5 OR Prime)
P(Even OR Odd)
Incl.
Inclusive Example #1
M.E.
ME or Incl Examples
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06 Probability Review.notebook
October 18, 2013
Odds vs. Probability
A young child is looking into a gumball machine filled with yellow, red, orange and blue gumballs. There are 10 yellow, 7 red, 18 orange and 20 blue gumballs in the machine. If the child puts in a quarter, find the odds or probability of the following.
Answers
Find the Probability/Odds
Odds (yellow)
P(yellow)
Probability means:
Probability can be any fraction from 0 to 1.
Odds (not blue)
P(not blue)
Odds means:
Odds can be any fraction (ratio).
It can be a small fraction or an improper fraction
Odds vs. Probability
Formula Match
Simple Probability
"and" Probability
Mutually Exclusive
Inclusive
P(red or orange)
Examples
Homework:
Worksheet 4-6
Probability
Quiz Tomorrow
Tombstones Due: ____________
Odds
Drag the formula to the type of probability
Formula Match
Homework
4