How to solve domino sequence questions

How domino questions work

Each tile has two halves, and each half shows between 0 and 6 dots; a blank half counts as 0. The question shows tiles in a row, a circle or a grid and asks which tile completes the sequence.

Values wrap around: after 6 comes 0, then 1 again. So 5 plus 3 gives 1, not 8. Forgetting this is a common reason why a correct pattern leads to an answer that is not among the options.

A method for most sequences

Work through the same checks in the same order:

1. Find the reading order. Read a row from left to right. In a circle, most sequences run clockwise; if nothing fits, try the other direction.
2. Follow the top halves on their own, then the bottom halves. Write each one down as a short number series.
3. Look for a constant step such as +1, +2 or +3, remembering that the count wraps from 6 back to 0.
4. If the halves do not move independently, compare each tile with the one before it: one half may repeat the other half of the previous tile, or be the sum of both its halves.

Example: a steady step with a wrap

Try it before reading the explanation. Work on the top and bottom halves separately.

Example: each tile builds on the previous one

Here neither half rises by a fixed step, so compare each tile with the one before it.

Mistakes to watch for

Check the orientation of each tile. When the question keeps tiles upright, [1|6] and [6|1] are different answers.

Other common slips are counting a blank half as 7, forgetting the wrap from 6 to 0, reading a circle in the wrong direction and following only one half. Once you have a candidate, test it against every tile shown, not just the last two.