際際滷

際際滷Share a Scribd company logo
1.4

Sets of Outcomes and Trees
Random Experiment
and Sample Space
   A random experiment is an experiment with
    multiple possible outcomes.
    Ex: Rolling a die, 鍖ipping a coin

   A sample space is the set of collection of all
    those outcomes.
    Ex: For experiment of rolling a dice,
    SS = {1, 2, 3, 4, 5, 6}
Tree Diagram
   Tree Diagrams are a useful way to visually
    represent a multi-stage experiment and
    determine the sample space.
How to
make a Tree Diagram
   Let use this following experiment as the example for
    our tree:
    There is Urn A and Urn B. Urn A has balls
    numbered 1, 2, 3. Urn B has balls colored green and
    red. You choose an urn and draw a ball from it.


      A                       B
Tree Diagram
The branches of a tree represent outcomes of a particular stage.
I personally like to line up the outcome from the same stage
vertically:
   Stage 1: Select the Urn
    Stage 2: Pick the Ball




      The resulting Sample Space is {Bg, Br, A1, A2, A3}, a total of 5 elements.
Representing an outcome twice
   A common mistake many students make is to put
    down a repeated outcome multiple times. Lets say
    there are 2 green balls in urn B. You would still only
    have one branch representing both green balls.
    Making two separate branches for one outcome is
    incorrect:

B
Quiz 1.4.1
Quiz 1.4.1
   Consider the following experiment: Fred goes to
    dinner and have to pay the bill, which comes to
    $7. He has one $10, one $5, and three $1. He
    pull random bills out of the pocket until he has
    enough to pay. How many elements are in the
    sample space?

    A. 9
    B. 10
    C. 11
Quiz 1.4.1
   Consider the following experiment: Fred goes to
    dinner and have to pay the bill, which comes to
    $7. He has one $10, one $5, and three $1. He
    pull random bills out of the pocket until he has
    enough to pay. How many elements are in the
    sample space?

    A. 9
    B. 10
    C. 11
Quiz 1.4.1
   Consider the following experiment: Fred goes to
    dinner and have to pay the bill, which comes to
    $7. He has one $10, one $5, and three $1. He
    pull random bills out of the pocket until he has
    enough to pay. How many elements are in the
    sample space?

    A. 9
    B. 10
    C. 11

   Answer: C
Multiplication principle
   If you have a multi-stage experiment, with equal number of
    possibilities in each stage regardless of the previous stage,
    theres a simple way to calculate the number of element in
    sample space.

   For example, Bob goes to McDonald to get a Happy meal. He
    can choose cheeseburger, nuggets, or chicken sandwich for
    entr辿e, soft drink, juice or milk for the drink, and 4 different
    toys.

   The number of combinations he could get is 3 x 3 x 4 = 36.
    (3 entr辿e, 3 drinks, 4 toys)
Quiz 1.4.2
   Mike goes to subway and gets a sandwich. He
    can choose between 5 kinds of bread, 4 kinds of
    cheese, and 3 kinds of meat. How many
    different sandwiches does he have to choose
    from?

    A. 20
    B. 60
    C. 120
Quiz 1.4.2
   Mike goes to subway and gets a sandwich. He
    can choose between 5 kinds of bread, 4 kinds of
    cheese, and 3 kinds of meat. How many
    different sandwiches does he have to choose
    from?

    A. 20
    B. 60
    C. 120

   Answer: B
Summary
   De鍖nition:
       Random experiment
       Sample space

   How to make a Tree Diagram
       determine sample space

   Multiplication Principle
   Features
        27 Recorded Lectures
        Over 116 practice problems with recorded solutions
        Discussion boards/homework help
        Visit 鍖nitehelp.com to 鍖nd out more

     For special offers and additional content...
Follow us on twitter @鍖nitehelp        Become a fan on Facebook

More Related Content

Finite Math - Sets of Outcomes and Trees

  • 2. Random Experiment and Sample Space A random experiment is an experiment with multiple possible outcomes. Ex: Rolling a die, 鍖ipping a coin A sample space is the set of collection of all those outcomes. Ex: For experiment of rolling a dice, SS = {1, 2, 3, 4, 5, 6}
  • 3. Tree Diagram Tree Diagrams are a useful way to visually represent a multi-stage experiment and determine the sample space.
  • 4. How to make a Tree Diagram Let use this following experiment as the example for our tree: There is Urn A and Urn B. Urn A has balls numbered 1, 2, 3. Urn B has balls colored green and red. You choose an urn and draw a ball from it. A B
  • 5. Tree Diagram The branches of a tree represent outcomes of a particular stage. I personally like to line up the outcome from the same stage vertically:
  • 6. Stage 1: Select the Urn Stage 2: Pick the Ball The resulting Sample Space is {Bg, Br, A1, A2, A3}, a total of 5 elements.
  • 7. Representing an outcome twice A common mistake many students make is to put down a repeated outcome multiple times. Lets say there are 2 green balls in urn B. You would still only have one branch representing both green balls. Making two separate branches for one outcome is incorrect: B
  • 9. Quiz 1.4.1 Consider the following experiment: Fred goes to dinner and have to pay the bill, which comes to $7. He has one $10, one $5, and three $1. He pull random bills out of the pocket until he has enough to pay. How many elements are in the sample space? A. 9 B. 10 C. 11
  • 10. Quiz 1.4.1 Consider the following experiment: Fred goes to dinner and have to pay the bill, which comes to $7. He has one $10, one $5, and three $1. He pull random bills out of the pocket until he has enough to pay. How many elements are in the sample space? A. 9 B. 10 C. 11
  • 11. Quiz 1.4.1 Consider the following experiment: Fred goes to dinner and have to pay the bill, which comes to $7. He has one $10, one $5, and three $1. He pull random bills out of the pocket until he has enough to pay. How many elements are in the sample space? A. 9 B. 10 C. 11 Answer: C
  • 12. Multiplication principle If you have a multi-stage experiment, with equal number of possibilities in each stage regardless of the previous stage, theres a simple way to calculate the number of element in sample space. For example, Bob goes to McDonald to get a Happy meal. He can choose cheeseburger, nuggets, or chicken sandwich for entr辿e, soft drink, juice or milk for the drink, and 4 different toys. The number of combinations he could get is 3 x 3 x 4 = 36. (3 entr辿e, 3 drinks, 4 toys)
  • 13. Quiz 1.4.2 Mike goes to subway and gets a sandwich. He can choose between 5 kinds of bread, 4 kinds of cheese, and 3 kinds of meat. How many different sandwiches does he have to choose from? A. 20 B. 60 C. 120
  • 14. Quiz 1.4.2 Mike goes to subway and gets a sandwich. He can choose between 5 kinds of bread, 4 kinds of cheese, and 3 kinds of meat. How many different sandwiches does he have to choose from? A. 20 B. 60 C. 120 Answer: B
  • 15. Summary De鍖nition: Random experiment Sample space How to make a Tree Diagram determine sample space Multiplication Principle
  • 16. Features 27 Recorded Lectures Over 116 practice problems with recorded solutions Discussion boards/homework help Visit 鍖nitehelp.com to 鍖nd out more For special offers and additional content... Follow us on twitter @鍖nitehelp Become a fan on Facebook

Editor's Notes