Question 1
In how many ways can students stand in a line?
Step-by-Step Solution:
Concept: Linear permutation of n distinct objects = n! (n factorial)
Analysis:
- We need to arrange 5 distinct objects in a line
- For the first position: 5 choices
- For the second position: 4 choices (one already placed)
- For the third position: 3 choices
- And so on...
Formula Application:
Number of arrangements = 5! = 5 × 4 × 3 × ... × 2 × 1
Calculation:
5! = 120
Key Concept: The factorial function represents the number of ways to arrange n distinct objects in a sequence.
Common Mistake: Don't confuse permutation (arrangement matters) with combination (arrangement doesn't matter).
Concept: Linear permutation of n distinct objects = n! (n factorial)
Analysis:
- We need to arrange 5 distinct objects in a line
- For the first position: 5 choices
- For the second position: 4 choices (one already placed)
- For the third position: 3 choices
- And so on...
Formula Application:
Number of arrangements = 5! = 5 × 4 × 3 × ... × 2 × 1
Calculation:
5! = 120
Key Concept: The factorial function represents the number of ways to arrange n distinct objects in a sequence.
Common Mistake: Don't confuse permutation (arrangement matters) with combination (arrangement doesn't matter).