Target Exam

CUET

Subject

General Aptitude Test

Chapter

Quantitative Reasoning

Topic

Permutation & Combination

Question:

In how many different ways can the letters of the word 'DELETE' be arranged?

Options:

36

120

33

720

Correct Answer:

120

Explanation:

The correct answer is Option (2) → 120

1. Analyze the word

First, count the total number of letters and identify any repeating letters:

  • Total number of letters (n): 6 (D, E, L, E, T, E)
  • Repetitions: The letter 'E' appears 3 times.
  • All other letters (D, L, T) appear only once.

2. The Formula

The number of distinct arrangements of $n$ objects where $p$ objects are of one type, $q$ of another, and so on, is:

$\text{Arrangements} = \frac{n!}{p! \cdot q! \dots}$

3. Calculation

Substitute our values into the formula:

$\text{Arrangements} = \frac{6!}{3!}$

Now, calculate the factorials:

  • $6! = 6 \times 5 \times 4 \times 3 \times 2 \times 1 = 720$
  • $3! = 3 \times 2 \times 1 = 6$

$\text{Arrangements} = \frac{720}{6} = 120$

Correct Option: 120