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With or without (Posted on 2021-03-22)

Let N be a randomly selected number between 1 and 999,999 inclusive.

Is it more likely that N contains the digit 1 or that it does not?

No Solution Yet Submitted by Ady TZIDON

Rating: 4.5000 (2 votes)

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1 is the loneliest number (spoiler)

| Comment 3 of 5 |

The chance that any individual digit is 1 is 1/10.

So the chance that any individual digit is not 1 is 9/10.

The chance that they are all not 1 is almost exactly (.9)^6 which is about 53%.

So, Ni is more likely to NOT contain the digit 1.

(Note, (.9)^6 would have been exact if the range was 0 to 999,999)

Posted by Steve Herman on 2021-03-22 08:18:27

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