Find all digits x (0–9) such that the three-digit number 2×4 is divisible by both 3 and 4.
Note
Divisible by 4 requires the last two digits x4 to be divisible by 4 (possible x = 0,2,4,6,8); divisible by 3 requires 2+x+4 divisible by 3 so x ≡ 0 (mod 3), giving x = 0 or 6. Thus x = 0 and 6.