Practise: Finned Fish
Follow one digit only: where is the extra fin, and which note disappears inside its box?
The prepared notes show the Fish and its fin. Check only the cross-line through the matching Fish corner in the fin’s box; do not place a digit yet.
Example 1 of 4
Your turn first
Where can 5 no longer stay?
In the prepared 5-notes, first find the almost-complete Fish. Then find the fin and matching corner in its box. Only there can another 5-note disappear.
Remember
A Finned Fish is simple: the extra fin keeps one possible home outside the base pattern. Only the matching cross-line inside that fin’s box is forced, so that is the only place where the digit can be removed.
Put it to use
Where you will meet it
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