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    IB Math AASL
    /
    Distributions & Random Variables
    /

    Video

    Video Reviews

    Watch comprehensive video reviews for most units, designed for final exam preparation. Each video includes integrated problems you can solve alongside detailed solutions.

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    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Distributions & Random Variables

    Video Reviews

    Watch comprehensive video reviews for Distributions & Random Variables, designed for final exam preparation. Each video includes integrated problems you can solve alongside detailed solutions.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    Not your average video:

    Interactive Problems: Solve problems alongside the video with step-by-step guidance and detailed solutions.

    Exam Preparation: Complete unit reviews designed for final exam preparation with all key concepts covered systematically.

    Expert Teaching: High-quality instruction from Perplex co-founder James Mullen with clear explanations, worked examples, and exam tips.

    HL

    The video will automatically pause when it reaches a problem.

    Probability Tables

    SL 4.7

    A discrete random variable takes from a finite set of values:

    X∈{x1​,x2​…xn​}


    Each possible value has an associated probability. These are often presented in a table:

    x

    1

    2

    3

    P(X=x)

    0.3

    0.5

    0.2

    Notice that the row of probabilities add to 0.3+0.5+0.2=1. This is called the law of total probability, and captures the since X must be one of these values, the probability of X being one of these values is 1.


    Example

    Find the value of k in the following probability distribution

    x

    1

    2

    3

    P(X=x)

    0.1

    k

    0.4


    By the law of total probability:

    0.1+k+0.4=1⇒k=0.5

    Probability Tables

    SL 4.7

    A discrete random variable takes from a finite set of values:

    X∈{x1​,x2​…xn​}


    Each possible value has an associated probability. These are often presented in a table:

    x

    1

    2

    3

    P(X=x)

    0.3

    0.5

    0.2

    Notice that the row of probabilities add to 0.3+0.5+0.2=1. This is called the law of total probability, and captures the since X must be one of these values, the probability of X being one of these values is 1.


    Example

    Find the value of k in the following probability distribution

    x

    1

    2

    3

    P(X=x)

    0.1

    k

    0.4


    By the law of total probability:

    0.1+k+0.4=1⇒k=0.5
    HL