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NDA Mathematics Permutation Combination 2026 NDA 2026 (Phase 1)

NDA Mathematics Question (2026) — Solution

Question

How many numbers greater than 1000 can be formed using the digits 0, 1, 2 and 3 (repetition of digits is not allowed) ?

Options

  1. A. 24
  2. B. 18
  3. C. 15
  4. D. 12

Answer

B. 18

Step-by-step solution

To form a number greater than 1000 using the digits 0, 1, 2, 3 without repetition, the number must be a 4-digit number. The thousands place cannot be 0, so it can be filled in 3 ways (using 1, 2, or 3). The remaining 3 places can be filled with the remaining 3 digits in 3! ways. Total number of such numbers = 3 3! = 3 6 = 18. Answer: 18

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