AMC 10 Weekly Practice Round 3
Complete problem set with solutions and individual problem pages
Problem 9 Medium
There are cars to be parked in adjacent parking spaces. Truck A is wider and occupies two spaces when parked, and car B cannot be parked next to truck A. How many different parking arrangements are there?
- A.
- B.
- C.
- D.
- E.
Answer:A
First, park truck .
 
If truck is not at the edge, there are possible positions. In this case, car B has possible positions. The other three cars (excluding A and B) can be arranged in ways.
 
If truck A is at the edge, there are possible positions. In this case, car B has possible positions. The other three cars can also be arranged in ways.
 
Therefore, the total number of parking arrangements is
 
Thus, the answer is .
