The product of all digits of positive integer M is 105. How many such Ms are there with distinct digits?
Possible digits
3 5 7
Arranging these in 3! ways we get 6 M's
Also
1 3 5 7
Arrranging these in 4! ways we get 24 more
So
24 + 6 =
30 possible M's
Thank you soo much!!!
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