Maths · Class 11 · Chapter 6
Permutations and Combinations
11 lessons102 min6 simulations
This chapter counts without listing. It starts from the multiplication principle and counting in cases, introduces factorials, and builds the formulas for permutations (arrangements, where order matters), including arrangements with conditions and with repeated objects. It then covers combinations (selections, where order does not matter), their properties and Pascal's rule, selections with conditions, problems that select and then arrange, and dictionary order.
Also called: P&C · counting · nPr and nCr
Lessons
11 lessons · 102 min
01The multiplication principleNCERT §6.1, §6.27 min02Counting in casesNCERT §6.27 min03Factorial notationNCERT §6.3.27 min04Permutations of distinct objectsNCERT §6.3, §6.3.1, §6.3.311 min1 sim05Arrangements with conditionsNCERT §6.3.310 min1 sim06Permutations with repeated objectsNCERT §6.3.49 min1 sim07CombinationsNCERT §6.49 min1 sim08Properties of combinationsNCERT §6.410 min1 sim09Selection with conditionsNCERT §6.47 min10Selecting then arranging, and dictionary orderNCERT §6.410 min1 sim11Chapter reviewMust-know facts, traps and formulas15 min
Simulations
6 in this chapter
Fill the places, then countIn: Permutations of distinct objectsGlue them together, or keep them apartIn: Arrangements with conditionsTag the twins, then take the tags offIn: Permutations with repeated objectsSelections, and the orders inside themIn: CombinationsPatterns in the table of nCrIn: Properties of combinationsWhere a word sits in the dictionaryIn: Selecting then arranging, and dictionary order