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## Question

Find the 9 digit number it

1. digits 1-9 appear once

2. the whole number is divisible by 9

3. remove the last digit of the whole number and it will be divisible by 8

4. remove the last 2 digits from the whole number and it will be divisible by 7

5. this pattern will continue to a single digit

This is kinda what i mean

abcdefghi/9

abcdefgh/8

abcdefg/7

What is the 9 digit number?

Edited by laine

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If I understand this...

```
381654729

381654729 / 9 = 42406081

38165472 / 8  = 4770684

3816547 / 7   = 545221

381654 / 6    = 63609

38165 / 5     = 7633

3816 / 4      = 954

381 / 3       = 127

38 / 2        = 19

3 / 1         = 3

```

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134568729 9 14952081

13456872 8 1682109

1345687 7 192241

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134568729 9 14952081

13456872 8 1682109

1345687 7 192241

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If I understand this...

I also got 381654729 to be the answer.

I used a pretty obtuse method for solving this problem, though. Would anyone be willing to share how they found the answer?

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I used a simple program running 9 for loops. 5 using odd numbers only and 4 using even, and tested all the combinations. It took 2 mins to write and 5 seconds for my comp to spit it out.

If I understand this...

I also got 381654729 to be the answer.

I used a pretty obtuse method for solving this problem, though. Would anyone be willing to share how they found the answer?

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I have a simple solution

1 is divisible by1

12 is divisible by 2

123 is divisible by 3

1234 is divisible by 4

12345 is divisible by 5

123456 is divisible by 6

1234567 is divisible by 7

12345678 is divisible by 8

123456789 is divisible by 9

Any mistake in this?

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I think the spirit of the OP was that the numbers would divide into integer numbers. While 1234 is divisible by 4, the solution has a fractional part.

I have a simple solution

1 is divisible by1

12 is divisible by 2

123 is divisible by 3

1234 is divisible by 4

12345 is divisible by 5

123456 is divisible by 6

1234567 is divisible by 7

12345678 is divisible by 8

123456789 is divisible by 9

Any mistake in this?

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381654729

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Is the second condition (divisible by 9) needed in this case? It goes without saying, doesn't it?

Edited by roolstar
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134568729 9 14952081

13456872 8 1682109

1345687 7 192241

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