Tie the two illegals together and pretend they're one person(a huge obese person or a typical American). Then there are 8! ways to arrange the other 8. They can be arranged in 2! ways.

There are9!*2! ways

3d) The probability that a rider is riding illegally is 5%. 200 controlls will be taking place. What is the probability that at least 7 and at most 12 illegal riders will be caught?