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Dependent and independent variables exercise example 1

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    On your math quiz, you earn
    5 points for each question
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    that you answer correctly.
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    In the table above, q represents
    the number of questions
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    that you answer correctly
    on your math quiz,
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    and p represents the
    total number of points
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    that you score on your quiz.
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    The relationship between
    these two variables
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    can be expressed by the
    following equation--
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    p is equal to 5q, where
    p is the points you get
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    and q is the number of questions
    you answered correctly.
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    And you could see
    that in the table.
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    If q is 0, if you got
    no questions right,
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    you get 0 points.
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    If you got no questions
    right, well, 5 times 0
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    is going to be 0.
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    If you get one question
    right, well, 1 times 5 is 5.
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    You get 5 points per question.
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    Two questions right,
    well, 2 times 5 is 10.
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    3 times 5 is 15.
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    So this all makes sense.
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    So then they ask us, which
    of the following statements
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    are true?
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    Check all that apply.
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    So let's think about this.
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    They say the
    dependent variable is
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    the number of points you score.
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    So when you think about
    what's happening here,
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    is your number of
    points you score
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    is being driven by how many
    questions you get right.
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    It's not like somehow the
    teacher says you got 15 points
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    and now you have to get
    exactly three questions right.
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    It's the other way around.
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    The number of
    questions you get right
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    is the independent
    variable, and that's
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    driving the number
    of points you score.
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    So the number of
    points you score
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    is the dependent variable.
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    And typically, the convention is
    to have the dependent variable
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    be equal to some
    expression involving
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    the independent variable.
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    And you see that
    right over here.
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    p is dependent on
    what happens to q.
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    Depending on the
    number of questions,
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    you multiply it by
    5, and you get p.
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    So the dependent variable is
    the number of points you score.
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    The dependent
    variable is the number
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    of questions you
    answer correctly.
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    No, we've already
    talked about that.
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    That's the independent variable.
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    The independent variable is
    the number of points you score.
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    No, that's not right.
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    That's the dependent variable.
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    The independent
    variable is a number
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    of questions you
    answer correctly.
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    Well, that's right.
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    That's what's driving
    the dependent variable.
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    And we can check our answer.
Title:
Dependent and independent variables exercise example 1
Description:

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Video Language:
English
Team:
Khan Academy
Duration:
02:10

English subtitles

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