Q. |
How many 9 digit numbers are there in which all the digits are distinct? |
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A. 9 x 9! |
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B. 9 x 8! |
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C. 9! |
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D. 8! |
First place can be filled in 9 ways
Hence total number = 9 × 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 = 9 × 9 !