Perplex
Content
  • Exponents & Logarithms
  • Approximations & Error
  • Sequences & Series
  • Matrices
  • Complex Numbers
  • Financial Mathematics
  • Cartesian plane & lines
  • Function Theory
  • Modelling
  • Transformations & asymptotes
  • 2D & 3D Geometry
  • Voronoi Diagrams
  • Trig equations & identities
  • Vectors
  • Graph Theory
  • Probability
  • Descriptive Statistics
  • Bivariate Statistics
  • Distributions & Random Variables
  • Inference & Hypotheses
  • Differentiation
  • Integration
  • Differential Equations
Other
  • Review Videos
  • Formula Booklet
  • Blog
  • Landing Page
  • Sign Up
  • Login
  • Perplex
    IB Math AIHL
    /
    Distributions & Random Variables
    /

    Binomial Distribution

    Edit

    Exercises

    Key Skills

    Binomial Distribution

    Binomial Distribution

    Concept of the binomial distribution, binomial PDF and CDF, expectation and variance of binomial distribution

    Want a deeper conceptual understanding? Try our interactive lesson! (Plus Only)

    Exercises

    No exercises available for this concept.

    Practice exam-style binomial distribution problems

    Key Skills

    The Concept of a Binomial Distribution
    SL 4.8

    The binomial distribution models situations where the same action is repeated multiple times, each with the same chance of success. It has two key numbers: the number of attempts (​n​) and the probability of success in each attempt (​p​).


    If a random variable ​X​ follows a binomial distribution, we write ​X∼B(n,p).

    Binomial PDF with calculator
    SL 4.8

    The binomial probability density function (aka pdf) is a function that models the likelihood of obtaining ​k​ successes from ​n​ trials where the likelihood of success of each trial is ​p. We calculate the probability of exactly ​k​ successes in ​n​ trials, ​P(X=k), using the calculator's binompdf function.


    Press 2nd ​→​ distr ​→​ binompdf(. Once in the binompdf function, write your ​n​ value after "trials," your ​p​ value after "p," and your ​k​ value after "x value." Then hit enter twice and the calculator will return the probability you are interested in.


    The distr button is located above vars . Once in the distr menu, you can also click alpha ​→​ A to navigate to the binompdf function.

    Binomial CDF with Calculator
    SL 4.8

    The binomial cumulative density function tells us the probability of obtaining ​k​ or fewer successes in ​n​ trials, each with a likelihood of success of ​p. We calculate the probability of less than or equal to ​k​ successes in ​n​ trials, ​P(X≤k), using the calculator's binomcdf function.


    Press 2nd ​→​ distr ​→​ binomcdf(. Once in the binomcdf function, write your ​n​ value after "trials," your ​p​ value after "p," and your ​k​ value after "x value." Then hit enter twice and the calculator will return the probability you are interested in.


    The distr button is located above vars . Once in the distr menu, you can also click alpha ​→​ B to navigate to the binomcdf function.

    Expectation and Variance of Binomial Distribution
    SL 4.8

    If ​X∼B(n,p), then

    ​
    E(X)=np📖
    ​

    and

    ​
    Var(X)=np(1−p)📖
    ​