Domino

After cataloging all 27 dominoes in the image, the full set of 28 standard double-six dominoes was compared against the observed tiles. All doubles ([0,0] through [6,6]) are present. All combinations for numbers 1, 2, 3, 4, and 5 are accounted for. When checking combinations for 6, the tiles [6,1], [6,2], [6,3], [6,4], [6,5], and [6,6] are all visible, but the [6,0] (six-blank) tile is missing.

After systematically cataloging all 27 dominoes visible in the image, I identified that the domino [2, 4] is missing from the standard 28-tile double-six set. The missing domino would have 2 dots on one half and 4 dots on the other half.

I systematically cataloged all visible dominoes in the image. A standard double-six set has 28 tiles. After identifying all 27 visible tiles and checking which combination from 0-0 through 6-6 is missing, the [0,3] domino (blank-three) is not present in the image.

The excluded domino is number 2 and 1

I identified all 28 possible domino pairs from 0–6 except the double six; every other double (0–0 through 5–5) and every mixed pair (0–1 through 5–6) appears in the image, so [6,6] is missing.

After carefully analyzing the image and counting the pips on each of the 27 dominoes shown, all possible combinations from 0-0 to 6-6 are present except for the domino with 3 pips on one half and 5 pips on the other.

After systematically identifying all dominoes in the image, I found all doubles except [6,6]. The doubles present are: [0,0] (row 5), [1,1] (row 4), [2,2] (row 3), [3,3] (row 1), [4,4] (row 2), and [5,5] (row 5). The domino [6,6] does not appear in the set. Additionally, all other dominoes with 6 are accounted for: [0,6], [1,6], [2,6], [3,6], [4,6], and [5,6], confirming that only [6,6] is missing.