1. Digit sum
8 + 1 + 1 + 8 = 18.
Rules mastery (4-digit N)
3 visual steps / divisibility rule
2. Multiple of 9
18 divisible by 9.
3. Answer yes
answer yes.
Practice Level 30
Use the visible move, then type only when the answer is clear.
Start Level3 visual steps / divisibility rule
8 + 1 + 1 + 8 = 18.
18 divisible by 9.
answer yes.
Use the visible move, then type only when the answer is clear.
Start Level