Question 1036845
The sum can't be odd, because then it wouldn't be divisible by 2.
Therefore, only even digits or odd digits are allowed.
11,13,15,17,19--13 works and 31
20,22,24,26,28----26 works and 62
31,33,35,37,39----39 works and 93
40,42,44,46,48--no
51,53,55,57,59--no
yx
y+x=2(y-x)
y+x=2y-2x
3x=y
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y+x=2(x-y)
y+x=2x-2y
x=3y
6 numbers are possible