Stage 32 · Counting, Permutations, Combinations & the Binomial Theorem

32.2.4 Permutations with Restrictions (I)

32.2 Permutations: When Order Counts Too

Point 4 of 6

32.2.4 Permutations with Restrictions (I)

Core idea

Someone must stand at the front, someone can't be at the back: settle the 'special spot or special person' first, then arrange everyone else

Module goal. Understand counting where the selection is ordered, master the permutation formula and factorials, and learn to spot permutation problems that carry restrictions
eastmath.com · 32.2 Permutations: When Order Counts Too · 32.2.4 Permutations with Restrictions (I)