In how many different ways can the letters of the word DISPLAY be arranged?
Aptitude
Permutation and Combination
Difficulty: Easy
Choose an option
-
A720
-
B1440
-
C2520
-
D5040
-
ENone of these
Answer
Correct Answer: 5040
Explanation
### Concept & Logic
When a word consists of $n$ distinct letters, the number of ways they can be arranged in a line is given by $n!$ (n factorial).
$$P = n!$$
### Step-by-Step Solution
- **Given:** The word 'DISPLAY'.
- Count the total number of letters: D, I, S, P, L, A, Y. There are $7$ letters.
- Check for repetition: All letters in the word are perfectly distinct from one another.
- Calculate the total permutations: $7! = 7 \times 6 \times 5 \times 4 \times 3 \times 2 \times 1$.
- Multiplication yields $5040$.
### Exam Strategy & Shortcut
Memorize the factorials up to $7!$ (where $5!=120$, $6!=720$, $7!=5040$). Recognizing the word length immediately yields the answer without requiring manual multiplication on paper.
### Common Pitfall
Miscounting the number of letters in the word or accidentally skipping a digit when multiplying the factorial sequence out manually.
### Final Answer
Therefore, the correct answer is **5040**.