A-level · Statistical distributions

The binomial distribution as a modelExam-style questions

When the count of "successes" in a fixed number of repeated trials follows a binomial distribution X ~ B(n, p): the four conditions (a fixed number of trials, two outcomes per trial, a constant probability of success, and independent trials), how to identify n and p from a context, how to state a condition for a binomial model, and when the binomial is NOT appropriate.

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18 questions · A-level level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 2Level 3Level 4
  1. 1
    A fair die is rolled 1010 times. XX is the number of sixes.
    (a) State the distribution of XX.
    (b) Find P(X=2)P(X = 2), to 4 d.p.
    Level 2 · 3 marksTry it
  2. 2
    State the four conditions that must hold for a variable to follow a binomial distribution.
    Level 2 · 2 marksTry it