Maths-
General
Easy
Question
The number of different seven digit numbers that can be written using only the three digits 1, 2 and 3 with the condition that the digit 2 occurs twice in each number is-
- 7P2 . 25
- 7C2 . 25
- 7C2 . 52
- None of these
The correct answer is: 7C2 . 25
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