Six mobsters have arrived at the theater for the premiere of the film "Goodbuddies." One of the mobsters, Frankie, is an informer, and he's afraid that another member of his crew, Joey, is on to him. Frankie, wanting to keep Joey in his sights, insists upon standing behind Joey in line at the concession stand, though not necessarily right behind him. How many ways can the six arrange themselves in line such that Frankie's requirement is satisfied?
6
24
120
360
720
5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
Mobsters
This topic has expert replies
-
Leon1984
- Senior | Next Rank: 100 Posts
- Posts: 32
- Joined: Sun Oct 18, 2009 5:23 pm
- Location: Israel
- Thanked: 3 times
- GMAT Score:640
First, let's see in how many ways we can arrange them with no restrictions: the number of ways to arrange 6 in a line is 6! = 720
What are the restrictions? F needs to be behind J. Since they are 6, and don't need to be one exactly after the other, there is equal amount of combinations in which this condition is met or not met, so it's 720/2=360.
Is it D?
What are the restrictions? F needs to be behind J. Since they are 6, and don't need to be one exactly after the other, there is equal amount of combinations in which this condition is met or not met, so it's 720/2=360.
Is it D?
Leon
