11 friends are living in 11 different flats of an apartment. Each of them was allotted a parking spot to park their cars in the ground floor. But they used to park their cars randomly in any of the 11 parking spots. In how many ways can they park their cars so that exactly 9 people park their cars in the spots allotted to them?
Choose the correct option: A) 40 B) 45 C) 50 D) 55 E) 60
11C9 = 55   The remaining 2 people in each case will be parked in each other's parking spots.   The answer is 55.
<result>D</result>
11 friends are living in 11 different flats of an apartment. Each of them was allotted a parking spot to park their cars in the ground floor. But they used to park their cars randomly in any of the 11 parking spots. In how many ways can they park their cars so that exactly 9 people park their cars in the spots allotted to them?