6 persons A,B,C,D,E,F are arranged in row. Find the conditional probability that C & D are separated given that A & B are together. 6.

Eight persons A, B, C, D, E, F, G and H appeared for an inter view. Find the probability that both A and D are selected in the interview?

A,A,B,B,C,C,D,E,F are arranged in a row so that no two alike alphabets are together. Find number of such arrangment

5 persons A, B, C, D and E are in a queue of a shop. The probability that A and E always occur together is

5 persons A, B, C, D and E are in a queue of a shop. The probability that A and E always occur together, is

Find the number of ways of arranging six persons (having A,B,C and D among them) in a row sothat A,B,C and D are always in order ABCD( not necessarily together).

Find the number of ways of arranging six persons (having A, B, C and D among them) in a row sothat A, B, C and D are always in order ABCD (not necessarily together).