Ex 6.3 Q9 Class 11 Maths Chapter 6 PnC | MONDAY Word Formation— (4-letter / 6-letter / Vowel-first)

In this video we solve all three parts of Question 9 Exercise 6.3 from Class 11 Maths NCERT Chapter 6 — Permutations & Combinations (PnC). Question: From the letters of the word MONDAY (all distinct), how many words (with or without meaning) can be made, assuming no letter is repeated, if: (i) 4 letters are used at a time, (ii) all letters are used, (iii) all used but first letter is a vowel? 🔢 Algorithm (step-by-step thinking — exam style) Part (i) — 4 letters used at a time Rule: Order matters → use permutation P(6,4). Algorithm: choose sequentially: first place 6 choices → second 5 → third 4 → fourth 3 → multiply. Part (ii) — all letters used Rule: all letters distinct and all used → use factorial 6!. Algorithm: arrange 6 distinct objects → multiply 6 × 5 × 4 × 3 × 2 × 1. Part (iii) — all used but first letter a vowel Identify vowels (O, A) → choose first letter (2 choices). Arrange remaining 5 letters in remaining slots → 5! ways. Algorithm: multiply choices for first letter × permutations of remaining positions. 🎯 Final Answers (quick) (i) P(6,4)=6×5×4×3=360 (ii) 6!=720 (iii) 2×5!= 2×120=240 💡 Why watch this video (exam benefits) Learn the decision rule: Order matters → permutation; all distinct & all used → factorial. Practice the sequential-choice algorithm so you can compute quickly in board exams, JEE Main, and CUET. Shortcuts and mental-multiplication tips to save time under pressure. 👉 If this helped, Like, Share, and Subscribe for more NCERT Class 11 concept videos. #Class11Maths #PermutationsAndCombinations #MONDAY #Exercise6_3 #NCERT #JEEMainTips #CUETPrep #MathsWithLogic