Q110
10 books are placed at random in a shelf. The probability that a pair of books will always be together is -
A.
B.
C.
Answer
D.
Answer: Option C
Solution
Answer: Option C
Solution:
10 books can be rearranged in 10! ways consider the two books taken as a pair then number of favourable ways of getting these two books together is 9! 2!∴ Required probability =