If `N` is the number of ways in which a person can walk up a stairway which has 7 steps if he can take 1 or 2 steps up the stairs at a time then the value of `N//3` is _______.

The number of ways in which a 7 people can sit around a round table is

The number of ways in which a couple can sit around a table with 6 guests if the couple takes consecutive seats is

The number of ways in which a couple can sit with 10 guests in a row if the couple takes consecutive seats is

There are 3 men and 7 women taking a dance class. If N ils number of different ways in which each man be paired with a women partner, and the four remaining women be paired into two pairs each of two, then the value of N//90 is_________.

The number of ways in which 7 people can sit around a table if two persons take consecutive seats is

If the number of ways in which the letters of the word ABBCABBC can be arranged such that the word ABBC does not appear is any word is N , then the value of (N^(1//2)-10) is_________.

Find the number of ways in which six persons can be seated at a round table, so that all shall not have the same neighbours n any two arrangements.

Let P_n denotes the number of ways in which three people can be selected out of 'n' people sitting in a row, if no two of them are consecutive. If P_(n+1)- P_n=15 then the value of 'n is____.

Find the number of ways in which 5A^(prime)sa n d6B ' s can be arranged in a row which reads the same backwards and forwards.

The number of ways in which 5 ladies and 7 gentlemen can be seated in a round table so that no two ladies sit together, is