Question

if six students what to sit at a circular table and Anna and Kelly must sit together, how many different arangements can occur?

Answer 1

(a)

For 6 students without any restriction:

Number of different arrangements is given by:

So,

Answer is :

120

(b)

If Anna and Kelly must sit together, consider Anna and Kelly as a single student.

So,

we get:

Number of different arrangements is given by:

Now Anna and Kelly can be permuted in 2! = 2 ways.

So,

Number of different arrangements with Anna and Kelly together is given by:

24 X 2= 48

So,

Answer is :

48