JEE Main 2023 (Online) 6th April Evening ShiftQuestion 1
All the letters of the word PUBLIC are written in all possible orders and these words are written as in a dictionary with serial numbers. Then the serial number of the word PUBLIC is
Permutation and Combination
Solution
Letters sorted: B,C,I,L,P,U. Rank of PUBLIC: words starting with B,C,I,L: $4\cdot120=480$. Starting with P: second letter B,C,I,L precede U: $4\cdot24=96$. PUB then remaining C,I,L: words PUBC.. and PUBI.. precede: $2\cdot2=4$. Then PUBL with C,I: PUBLCI precedes (1). Rank $=480+96+4+1+1=582$. Option D.