Mathematics 9709 · AS & A Level · The Poisson distribution
The Poisson distribution — practice question
Determine how many different numbers can be formed from some or all of the digits of the number $1\,345\,789$ if
(i)[2]
all seven digits are used, the odd digits stay together and no digit is repeated,
(ii)[3]
the numbers formed are even numbers between $3000$ and $5000$, and no digits are repeated,
(iii)[3]
the numbers formed are multiples of $5$ which are less than $1000$, and digits can be repeated.
Worked solution & mark scheme
This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: “A correct appearance of $5!$ or $3!\times5!$ or $6!$” …