There is no digit that can replace the ? in 2?67 to make it divisible by 4.
All multiples of 4 are even, 2?67 is an odd number and so cannot be a multiple of 4.
0.
Add 6 to it and so 8784/18 = 488
29 is not divisible by 3 and how any digit will alter that depends on how that digit is to interact with 29.
99996
If the number is divisible by 9 the sum of its digits (its digital root) must be divisible by 9. 5+6+8+9 = 28 The next multiple of 9 is 36 and that is 8 more. So the missing digit must be 8.
It depends on whether you mean the highest digit that you add or subtract or multiply by!
The 3, to the left.
No single digit determines divisibility by 3.
6 (or 0)
123456
4: to make it 90144 = 15024*6
Any integer divisible by 9 has digits whose sum is divisible by 9. The sum of the digits in 2530 is 2+5+3+0 = 10, and the sum of 1+0 = 1. Having an additional digit "8" in the number, or replacing the "0" with an "8", would make a number divisible by 9. Thus 82,530; 28,530; 25,830; 25,380; 25,308; or 2,538 are all divisible by 9.