Mathematics 9709 · AS & A Level · The Poisson distribution

The Poisson distribution — practice question

The distribution of the random variable $X$ is $\text{Po}(25)$.
(a)[4]

Apply the normal approximation to the Poisson distribution to determine $P(X > 30)$.

(b)[2]

Let $Y$ have distribution $B(100, p)$ with $p < 0.05$. Use the Poisson approximation to the binomial distribution to write an expression, in terms of $p$, for $P(Y < 3)$.

Worked solution & mark scheme

This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “State that $X \sim N(25,25)$.” …

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