← The Logic Grid · Lesson 1 of 3
One of each
A logic-grid puzzle matches people to things, like three friends and three pets. Draw a grid: names down the side, pets across the top.
Each person has exactly one pet, and each pet belongs to exactly one person. So every row and every column ends with exactly one tick.
In a three-by-three grid, a row already has two crosses. What goes in its last box?
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