Mathematics 9709 · AS & A Level · The Poisson distribution
The Poisson distribution — practice question
Hebe works on a crossword puzzle each day. Let $X$ stand for how many puzzles she finishes in a week (7 days). On average, Hebe finishes $7$ out of $10$ of these puzzles.
(i)[2]
State two conditions needed for $X$ to be binomially distributed.
(ii)[3]
Use a binomial distribution to determine the chance that Hebe finishes at least $5$ puzzles in a week.
(iii)[3]
Use a binomial distribution to determine the probability that, over the next $10$ weeks, Hebe completes $4$ or fewer puzzles in exactly $3$ of the $10$ weeks.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “States that the probability of success stays constant” …