If the letters of the word 'PROBABILITY' are written down at random in a row, then probability that two B's are together, is

Step-by-step solution

Total number of ways in which the letters of the word 'PROBABILITY can be amanged in a row = 11! 2!2 ! Number of ways in which two B's are togother = 10! 2! Required probability = 10 2 ! 11! 2!2! = 10 ! 2! 11! = 2 11