Question 5

A mobile phone service provider is launching a new product with SIM card numbers consisting of $12$ digits. An employee is assigned to arrange the card numbers with a prefix code (the first four numbers of the mobile service provider's identity) being $0844$ and the last four digits being a "beautiful number," which is $1221$. The employee is only allowed to use the digits $2, 3, 4, 5, 7, 8, 9$ to arrange the card number. The number of card numbers that can be created by the employee is...