Mathematics 9709 · AS & A Level · The Poisson distribution
The Poisson distribution — practice question
For any given day, the chance that Julie’s train arrives late is $0.3$.
(i)[2]
State three requirements that a situation must meet to be represented by a binomial distribution.
(ii)[3]
A random selection of nine days is made. Find the probability that Julie’s train is late on more than $7$ of the days or on fewer than $2$ of the days.
(iii)[5]
A random sample of ninety days is taken. Find the probability that Julie’s train is late on more than $35$ days or on fewer than $27$ days.
Worked solution & mark scheme
This 10-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Correctly recognising the constant probability and the independent trials” …