Fives and Threes is a block dominoes game with a scoring rule bolted on. Tiles are matched end to end in a single line, and every time you place one you add up the spots on the two open ends and check whether that total divides by three, by five, or by both. That check, made after every placement, is where the points come from.
The rule in three lines
Add the spots on the two open ends of the line. Then:
- If the total divides by three, score the total divided by three. A total of 9 scores 3.
- If the total divides by five, score the total divided by five. A total of 10 scores 2.
- If it divides by both, score both and add them. The only scoring total where that can happen in play is 15, which scores 5 + 3 = 8.
One further rule: a double at an open end counts both its halves, so a double-four there shows 8 spots, not 4. Nothing that is not an open end counts.
In Fives and Threes Dominoes the table shows the open-end totals and the points scored after each move, so you can check this arithmetic against the screen as you play.
Every total and what it scores
With a standard double-six set, a plain end shows 0 to 6 spots and a double at an end shows 0 to 12. The highest pair of ends is the double-six against the double-five, 22. Totals of 19 and 21 cannot be made: an odd total needs a plain end, at most 6, and the other end would then need 13 or more.
| Total | Divides by 3 | Divides by 5 | Score |
|---|---|---|---|
| 0, 1, 2, 4, 7, 8 | — | — | 0 |
| 3 | 1 | — | 1 |
| 5 | — | 1 | 1 |
| 6 | 2 | — | 2 |
| 9 | 3 | — | 3 |
| 10 | — | 2 | 2 |
| 11, 13, 14 | — | — | 0 |
| 12 | 4 | — | 4 |
| 15 | 5 | 3 | 8 |
| 16, 17 | — | — | 0 |
| 18 | 6 | — | 6 |
| 20 | — | 4 | 4 |
| 22 | — | — | 0 |
Nine of the 21 reachable totals score and twelve do not; zero divides by everything but is worth nothing. Fifteen is the top score by a clear margin, and 18 is next at 6, reachable only with a double at an end. The 20 needs two doubles at once, the double-six against the double-four, and the largest total, 22, scores nothing.
The quick mental check: is it 3, 5, 6, 9, 10, 12, 15, 18 or 20? If not, the placement scores nothing.
Worked example: one end, five choices
Say the open ends show 4 and 2, and you hold tiles that can go on the 2. The 4 stays put; the new end is the other half of the tile you lay.
- Play the 2-1. The ends become 4 and 1, total 5: 1 point.
- Play the 2-3. The ends become 4 and 3, total 7: nothing.
- Play the 2-5. The ends become 4 and 5, total 9: 3 points.
- Play the 2-6. The ends become 4 and 6, total 10: 2 points.
- Play the double-two. The end now shows both halves, 4 spots, against the 4: total 8, nothing.
Same end, and the score ranges from 0 to 3. The other end offers less: the double-four on the 4 makes 8 plus 2, 10, for 2 points. The 2-5 is best, and you only find it by running the sum for each tile.
The How to play screen in Fives and Threes Dominoes has a worked scoring example of its own if you want a second one.
Worked example: making 15
The ends show 6 and 3, and you hold the double-six. Laid crossways on the 6, it shows 12 spots, and 12 plus the 3 at the other end is 15: 8 points from one tile.
With both ends showing 5, the double-five on either end gives 10 against 5, and 8 points again. Two plain ends top out at 6 + 6 = 12, so every 15 needs a double at one end.
Worked example: covering a double
Doubles only count twice while they are an open end. Take the 15 just made: double-six at one end, 3 at the other. Your opponent plays the 6-2 against the double. The double is now inside the line, the new end shows 2, and the total is 2 plus 3, 5: 1 point to them. Had they held the 6-0 instead, the total would be 3, also worth 1; the 6-3 would make 6 and score 2.
A double at an end raises the totals available to whoever plays next, which is worth weighing before you lay one on a total that does not score.
Reading the position, not just the move
The score for any placement depends on two numbers: the end you leave alone and the new end you create. Before placing, look at the end you are not playing on and list the new ends that pair with it. Against a 4, the scoring new ends are a plain 1 (total 5), 2 (6), 5 (9) or 6 (10), or the double-one (6), double-three (10) or double-four (12). Against a 3, they are a plain 0 (3), 2 (5), 3 (6) or 6 (9), or the double-blank (3), double-one (5), double-three (9) or double-six (15). Then check which of those your hand can produce.
The same arithmetic tells you what you are leaving behind. The ends you create start your opponent's next sum, so a scoring move that leaves an easy 15 is worth less than it looks.
Fives and Threes Dominoes uses exactly this rule: divide by three, divide by five, both for 15, and a double at an open end counts both its spots. The table shows the open-end totals and the points scored after each move, ends that cannot take the selected tile are marked, and How to play includes a worked scoring example. You play solo against a computer opponent on Casual or Competitive, to a target of 61, 121, 181 or 241 points, with 6 to 9 tiles each and the going-out bonus on or off. There are no adverts or in-app purchases, and the match points are in-game only with no cash value.