JEE Main202311 Apr 2023Evening ShiftMathematicsPermutation and CombinationActual
If the letters of the word MATHS are permuted and all possible words so formed are arranged as in a dictionary with serial numbers, then the serial number of the word THAMS is
Options
- A103
- B102
- C101
- D104
Correct answer
A. 103
Step-by-step solution
The given word is MATHS Arranging the letters alphabetically, we get AHMST When the word starts with any of the letters A/H/M/S, the number of possibilities = 4 ! × 4 = 96 Now when the word starts with TA, then the number of possibilities = 3 ! = 6 Now when the word starts with THAMS, then the number of possibilities = 1 Rank = 96 + 6 + 1 = 103 Hence, rank of the work THAMS is 103 .