Question

Five different books (P, Q, R, S, T) are to be arranged on a shelf. The books R and S are to be arranged first and second, respectively from the right side of the shelf. The number of different orders in which P, Q and T may be arranged is _______.

• A. 12
• B. 2
• C. 120
• D. 6

Answer 1

The correct option is D 6

Here R and S are fixed in 1st and 2nd place from right.



Therefore arrangement of
$P,Q,T={}^3{P}_3=3!=6$