Question:
The number of three digit numbers which have at least two identical digits is
The number of three digit numbers which have at least two identical digits is
Show Hint
“At least” problems are easiest using complement method.
Updated On: Apr 15, 2026
- 648
- 729
- 252
- 452
Show Solution
Verified By Collegedunia
The Correct Option is C
Solution and Explanation
Concept:
Use complement counting.
Step 1: Total 3-digit numbers.
\[ 900 \]
Step 2: All digits different.
\[ 9 \times 9 \times 8 = 648 \]
Step 3: At least two same.
\[ 900 - 648 = 252 \]
Step 1: Total 3-digit numbers.
\[ 900 \]
Step 2: All digits different.
\[ 9 \times 9 \times 8 = 648 \]
Step 3: At least two same.
\[ 900 - 648 = 252 \]
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