there are five seats in a row, person A and person B are to

Question

there are five seats in a row, person A and person B are to sit in the seats. How many ways can person A and person B sit in the seats so that person A and B are adjacent?

SimaQ · Answer

Answer is 6 isn't it? ...3! Not very informative answer is it?

willget800 · Answer

5P2?

5 seats, and 2 people have to sit together.. and since the order does matter.. it has to be 5P2..

which is 20...

OA?

SimaQ · Answer

I believe what you calculate here is how many ways can five persons sit in first two places.....

SimaQ · Answer

The answer is not 6... it is 8......

Simple down to earth approach:

12 23 34 45
21 32 43 54

kook44 · Answer

No equations necessary here:

 
Seats: 1 2 3 4 5
 A B
 A B
 A B
 A B
 

That's 4, now multiply by 2 for when A & B are swithced...

giddi77 · Answer

Agree with 8 and also agree that no permultations, factorials, combinations.... are necessary!

ywilfred · Answer

There should be 8

Number the seats: 1,2,3,4,5

AB
12
23
34
45

That's 4 combinations. Then switch A and B around to get the other 4.

mand-y · Answer

Another 8 5 SEATS

___ ___ ___ ___ ___
A B
 A B
 A B
 A B

EACH OF THE 4 ARRANGEMENT HAS 2 COMBINATION AB 
 BA

SO 4X2

chiragr · Answer

no permutation combination needed...brute force calculation will work

A can sit in any of 1-5 chair
End chair B can sit in next chair only = 2 posibility
for middle three chair B can sit in to two chair = 3*2 = 6 posibilities

total 8!

SunShine · Answer

8.

My simple working also come to 8.

Saet 1 2 3 4 5
 when A is at 1 or 5 there is only one option for B, SO TOTAL 2

when A is at 2, 3, 4, there are 2 oprions each for B to seat, toatal 6

6+2 = 8

there are five seats in a row, person A and person B are to

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