JEE Mains · Maths · STD 11 - 6. permutation and combination
The total number of three-digit numbers, with one digit repeated exactly two times, is
- A \(256\)
- B \(289\)
- C \(243\)
- D \(237\)
Answer & Solution
Correct Answer
(C) \(243\)
Step-by-step Solution
Detailed explanation
If 0 taken twice then ways \(=9\) If 0 taken once then \({ }^{9} C _{1} \times 2=18\) If 0 not taken then \({ }^{9} C _{1}{ }^{8} C _{1} \cdot 3=216\) Total \(=243\)
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