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Perplex
Dashboard
Topics
Exponents & LogarithmsApproximations & ErrorSequences & SeriesFinancial Mathematics
Cartesian plane & linesFunction TheoryModelling
2D & 3D GeometryVoronoi Diagrams
ProbabilityDescriptive StatisticsBivariate StatisticsDistributions & Random VariablesInference & Hypotheses
DifferentiationIntegration
Review VideosFormula BookletMy Progress
BlogLanding Page
Sign UpLogin
Perplex
IB Math AISL
/
Distributions & Random Variables
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Problem Bank
IB Math AISL
/
Distributions & Random Variables
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Problem Bank

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[Maximum mark: 6]

James is sitting a multiple choice exam with ​12​ questions. Each question has ​5​ answer choices, of which only one is correct.

James randomly picks an answer on each question. Let ​X​ represent the number of questions James answers correctly.

  1. State whether ​X​ is discrete or continuous.

    [1]

    To earn a crown, get your answer ready before you reveal the options!

  2. Write down the value of ​E(X).

    [1]
  3. Find the probability that

    1. ​X=4,

    2. ​2<X<9.

      [4]
[Maximum mark: 6]

James is sitting a multiple choice exam with ​12​ questions. Each question has ​5​ answer choices, of which only one is correct.

James randomly picks an answer on each question. Let ​X​ represent the number of questions James answers correctly.

  1. State whether ​X​ is discrete or continuous.

    [1]

    To earn a crown, get your answer ready before you reveal the options!

  2. Write down the value of ​E(X).

    [1]
  3. Find the probability that

    1. ​X=4,

    2. ​2<X<9.

      [4]