Question 1196655
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If the first digit is 1, then the second digit must be 0 since "The first digit is larger than the second" is given to us. 
Therefore, this forms the number 10 as the only possibility for this case.


If the first digit is 2, then we could have either 20 or 21


If the first digit is 3, then we could have either 30, 31, or 32


If the first digit is 4, then we could have either 40, 41, 42, or 43


Here's the entire sample space
{
10
20,21
30,31,32
40,41,42,43
}
Each row has a different tens digit to help break things up better. 


Though if you wanted you can list everything on one single line like this
{10,20,21,30,31,32,40,41,42,43}


We can see that 10 is a potential answer choice, and so is something like 30 31 32
However something like 12 is NOT a potential answer.
Also, anything involving 5 isn't an answer since it's not in the range from 0 to 4.
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