Question 1
In how many ways can books be arranged on a shelf?
Step-by-Step Solution:
Concept: Linear permutation of n distinct objects = n! (n factorial)
Analysis:
- We need to arrange 4 distinct objects in a line
- For the first position: 4 choices
- For the second position: 3 choices (one already placed)
- For the third position: 2 choices
- And so on...
Formula Application:
Number of arrangements = 4! = 4 × 3 × 2 × ... × 2 × 1
Calculation:
4! = 24
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 4 distinct objects in a line
- For the first position: 4 choices
- For the second position: 3 choices (one already placed)
- For the third position: 2 choices
- And so on...
Formula Application:
Number of arrangements = 4! = 4 × 3 × 2 × ... × 2 × 1
Calculation:
4! = 24
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).