In how many different ways can the letters of the word JUDGE be arranged in such a way that the vowels always come together?
Aptitude
Permutation and Combination
Difficulty: Easy
Choose an option
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A48
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B120
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C124
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D160
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ENone of these
Answer
Correct Answer: 48
Explanation
### Concept & Permutations with Grouping
When a specific set of items must always appear together, we treat them as a single unit or "block". We then find the permutations of all units, and multiply this by the permutations of the items within the "block".
The general formula for arranging $n$ distinct items is $n!$. If items are grouped into 1 unit, the total units become $(n - k + 1)$ where $k$ is the size of the group.
### Step-by-Step Solution
* **Analyze the Word:** The word "JUDGE" contains 5 letters.
* **Identify Vowels and Consonants:**
* Vowels: U, E (2 letters)
* Consonants: J, D, G (3 letters)
* **Group the Vowels:** Since the vowels must be together, treat (UE) as a single unit.
* **Count the Units:** We now have the consonants J, D, G and the vowel unit (UE). This gives a total of $3 + 1 = 4$ units.
* **Arrange the Units:** The 4 units can be arranged in $4!$ ways.
* $4! = 4 \times 3 \times 2 \times 1 = 24$
* **Arrange Items Within the Unit:** The 2 vowels (U, E) can be arranged among themselves in $2!$ ways.
* $2! = 2 \times 1 = 2$
* **Calculate Total Arrangements:** Multiply the two results.
* Total ways = $24 \times 2 = 48$
### Exam Strategy & Shortcut
For simple non-repeating words, immediately write down (Total Consonants + 1)! $\times$ (Total Vowels)!. Here: $4! \times 2! = 24 \times 2 = 48$. This takes less than 15 seconds.
### Common Pitfall
A common mistake is forgetting to arrange the vowels within their own group. Students often calculate $4! = 24$ and stop there, resulting in an incorrect answer. Always account for internal permutations of the grouped block.
### Final Answer
Therefore, the correct answer is **48**.