Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Welcome to ALGEBRA!
Agenda 1) Log In to Nspire ­ Username is your name and Password 1234
2) Probability Do­Now 3) Questions from OTL 4) Skunk
5) Probability of 2 events 5) Spinners ­ Are they fair?
OTL: Tan pp. 41­43 #2­22 even
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
BELL RINGER Wk2Dy2
First, grab a large black calculator by the window. Then please pull out your spiral. Label the top of the page Bell Ringer. Then do the problems below. 1) If you roll heads 42 times in a row, what is the probability of rolling a tails on the next roll? 2) Ifyourolladice90times,howmanytimeswouldyouexpecta5?
3) Ifyoulipacoin314times,howmanytimeswouldyouexpecta
heads? What is the probability of heads on flip 315? 4)
Find the probability of throwing a dart and hitting red
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Key Vocabulary Experimental Probability ­ The # of times WON divided by the TOTAL # of times played Theoretical Probability ­ The # of ways to WIN divided by the TOTAL # of ways to play
Expected Value ­ The probability of an event multiplied by the number of occurrences. 3
Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
The Game of SKUNK
To start the game each player makes a score sheet like this:
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Each letter of SKUNK represents a different round of the game; play begins with the "S" column and continue through the "K" column. The object of SKUNK is to accumulate the greatest possible point total over five rounds. The rules for play are the same for each of the five rounds.
• At the beginning of each round, every player stands. Then, a pair of dice is rolled. • A player gets the total of the dice and records it in his or her column, unless a "double" comes up.
• If a "double" comes up, play is over for that round and all the player's points in that column are wiped out.
• If "double ones" come up, all points accumulated in prior columns are wiped out as well.
• If a "one" doesn't occur, the player may choose either to try for more points on the next roll (by continuing to stand) or to stop and keep what he or she has accumulated (by sitting down).
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Take time to answer the 'Thinking about SKUNK' questions
1) What are some strategies to score many points without losing them all?
2) What would have been helpful to know before playing the game?
3) On average, how many rolls did it take before we rolled a double?
4) How could we have used math before playing to make our strategy 'smarter' than just guessing?
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Time for some notes
Two event probability
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Probability Trees & Diagrams
When working with more than one event it is very helpful to make a diagram to find all the possibilities. Last year we studied Tree diagrams and an Outcome box. TREES
OUTCOME BOX
H T
H HH
HT
T
TT
TH
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Probability Trees & Diagrams
In your notes make a Tree diagram for flipping 3 fair coins. Let's Construct the Tree Together 9
Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Probability Trees & Diagrams
In your notes make a Outcome Box for rolling 2 dice. Questions to Answer when your box is complete:
1) Why did it seem like there was always a double being rolled?
2) Physically describe the location of the doubles in your box.
3) Physically describe the location of the 7's in your box.
4) Compare the probability of rolling a double to rolling a 7. Then compare their location in the box.
5) Compare the probability of rolling a 7 to that of rolling a 5. What is the significance of the location of the 7 and the doubles in relation to their probability or likelihood?
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Multiple Event Probability Notes
Let A and B be INDEPENDENT events. The probability of A and B both occurring simultaneously is the *product* of probability of A and the probability of B.
Create an example where event A is some probability of 1 dice and event B is some probability of a second dice. Be sure to make sense of your example with proper notation. 12
Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
P(H) n P(T) = What is the difference between P(H,T) = and P(H) n P(T) =
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Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Spinners
Instructions: At your seat create a tree or outcome box diagram that represents the possible outcomes of the spinners below. Then answer the questions below. There are 3 examples so you need 3 outcome boxes or trees. A
And When spinning each spinner in A only once,
1) What is the possibility of spinning double green?
2) What is the possibility of spinning orange on the first and Purple on the second? B
AND
When spinning each spinner in B only once,
1) Do the spinners have to be the exact same for us to use?
2) Are these spinners fair to use?
3) What is the possibility of spinning double 3?
4) What is the possibility of spinning a '2' on the first and '1' on the second? C
AND
When spinning each spinner in C only once,
1) Do the spinners have to be the exact same for us to use?
2) Are these spinners fair to use?
Suppose we use these to play a game think of a strategy to find the probability of each sector. 3) What is the possibility of spinning 3 and Blue?
4) What is the possibility of spinning a double Green? 14
Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
Journal Prompts
Create a section in your notes titled Journal. For the next 8 Minutes in your notes you will write a response to the prompts below. 1) Probability should be studied more in other classes because it helps me...
2) I learned the most about probability when... 15
Wk2Dy2 ­ Intro Two Event Probability (morrison).notebook
September 06, 2013
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