SOLUTION: Six students are lining up for flag ceremony. If three persons insist on standing next to each other, how many ways can the six students arrange themselves?
Algebra ->
Probability-and-statistics
-> SOLUTION: Six students are lining up for flag ceremony. If three persons insist on standing next to each other, how many ways can the six students arrange themselves?
Log On
Question 1108562: Six students are lining up for flag ceremony. If three persons insist on standing next to each other, how many ways can the six students arrange themselves? Found 2 solutions by josmiceli, Edwin McCravy:Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! The 3 that must be together can arrange
themselves 6 different ways:
a b c
a c b
b a c
b c a
c a b
c b a
P( 3,1 ) = 3! / 1!
P( 3,1 ) = 6
-----------------------
Each one of these 6 possible groupings can
fit into the arrangements of the other 3 students:
( think of the 3 that must be together as one
student that 6 different identities )
144 different ways
------------------------
Definitely get a 2nd opinion if needed
The trio that must stand together can be arranged in 3! = 6 ways.
Then for each of those 6 ways, we have 4 "things" to arrange.
[The 4 "things" consist of 3 single persons and 1 trio.]
That's 4! - 24 ways.
Answer: 3!∙4! = 6∙24 = 144
Edwin