Question

in how many ways can 5 person a,b,c,d and e sit around a circular table if (I) b and d sit next to each other (ii) a and d do not sit next to each other​

Answer 1

Answer:

A ξ B not sit together = Total −(AξBsittogether)

⇒ Total permutation =(5−1)!=4!=24

A ξ B sit together : AξB should be considered as 1 entity so now 4 entities to be seated =3!, But AξB can interchange their places,

∴3!×2!=12

⇒ Required =24−12=12

Hence, the answer is 12.