PERMUTATIONS AND COMBINATIONS | CIRCULAR PERMUTATIONS, PRINCIPLE OF INCLUSION AND EXCLUSION, PERMUTATIONS UNDER RESTRICTIONS | Circular permutation:Concept + Formula + clockwise /anticlockwise arrangements , 5 Boys and 5 girls sit alternately around a round table. In how many ways can this be done ?, A person invites a group of 10 friends at dinner and sits (i) 5 on a round table and 5 on other round table (ii) 4 on one round table 6 on other round table . Find no. of ways in each case in which he can arrange the guest?, What are the principle of inclusion & exclusion ? ex:- Find the no. of positive integers from 1 to 1000 which are divisible bY atleast 2;3 and 5 ., When particular objects are never together (Gap method) (i) Find the no. of ways in which 5 girls and 5 boys can be arranged in a row if no two boys together