NUMB3RS - Season 2 - "Soft Target" - Is This Seat Taken?
Topic: Combinatorics and Permutations • Difficulty: Algebra 2
Row Permutations & Factorials
When arranging distinct objects or people in a linear row, each decision reduces the number of available options for the next spot.
For example, if we have people sitting on a bench:
- The first seat can be filled by any of the people.
- The second seat can be filled by either of the remaining people.
- The final seat must be filled by the remaining person.
According to the Fundamental Counting Principle, the total number of unique ways to seat them is:
Now, let's scale this up. If we have people to seat in a row, how many unique linear seating arrangements are possible?
If there are 5 people to be seated in a row, how many different ways can they be seated?
Permutations Sandbox
Explore physical seating constraints live. Rotational symmetry, grouping restrictions, and alternating setups are represented interactively below.
Active Row Seating Factorial Formula:
5! = 5 • 4 • 3 • 2 • 1 = 120
Try changing your active step on the left. The visualizer matches the respective counting principle for your current workbook question.