This seems to be a very simple task, but I don’t know how it can be solved.
I have a lot of numbers: {1, 2, 3, 4, 5}. I need to calculate how many even 3-digit numbers I can get from these numbers.
The numbers in the number must not be repeated.
The first thing I want to do in this situation is to find the number of numbers that I can make up under a given condition.
It’s easy: 5 * 4 * 3 = 60
These are all numbers, but I only want the even ones.
For an hour now I have been unable to figure out how to solve this problem – even though it is simple.
I used an online application that generated all these 60 numbers, including 24 even ones.
If necessary, I will post it.
The question is: how to solve this problem mathematically?
