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The following question is based on the five three-digit numbers given below:

243      342      573      452      621
If the first and the second digits of each number are interchanged with each other, then what will be the smallest number?

  1. 452
  2. 573
  3. 243
  4. 621

Answer (Detailed Solution Below)

Option 4 : 621
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Detailed Solution

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Given numbers:

243      342      573      452      621

On interchanging the first and second digits of the numbers, we get

423      432      753      542      261

Hence, the smallest number is 261, which we get from 621.

Hence, 621 is the correct answer.

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-> The RRB Group D Exam Date will be announced on the official website. It is expected that the Group D Exam will be conducted in August-September 2025. 

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-> Check the latest RRB Group D Syllabus 2025, along with Exam Pattern.

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