MHB Find All Possible Solutions to $A$: 9 Digit Number

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The discussion focuses on finding a 9-digit number $A=abcdefghi$ where each digit is unique. The number must meet specific divisibility criteria: the first two digits are divisible by 2, the first three by 3, and so forth. Participants share potential solutions, including 381654729 and 801654723, while clarifying the requirement for distinct digits. The conversation highlights the challenge of adhering to the rules while generating valid numbers. Multiple solutions are acknowledged as possible.
Albert1
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$A=abcdefghi$ is a 9 digits number
the first 2 digits are divisible by 2
the first 3 digits are divisible by 3
---and so on
here: $ a,b,c,d,e,f,g,h,i$ are all different
please find $A$
(note :may be more than one solution)
 
Last edited:
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My solution:

381654729
did not know that i was not supposed to show my answer (Tmi)
 
Last edited:

Here's another.

[sp]
123,\!258,\!168
[/sp]
 
ineedhelpnow said:
...did not know that i was not supposed to show my answer (Tmi)

No worries! :D
 
soroban said:
Here's another.

[sp]
123,\!258,\!168
[/sp]
I am sorry,I did not make it clear
here a,b,c,d,e,f,g,h,i are all different
 
Albert said:
$A=abcdefghi$ is a 9 digits number
the first 2 digits are divisible by 2
the first 3 digits are divisible by 3
---and so on
here: $ a,b,c,d,e,f,g,h,i$ are all different
please find $A$
(note :may be more than one solution)
A=381654729, or A=801654723
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

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