Compare the pair rule

Each panel contains a first figure and a second figure. Compare what changes between them. Here an up arrow becomes a right arrow: it turns one quarter-turn clockwise.

The outline stays an outline and the dot count stays at one. Describe the whole change: turn clockwise once, keep the fill, keep the dots.

Turns use quarter-turn steps: zero, one, two or three clockwise steps. Three clockwise steps end in the same direction as one counterclockwise step.

Pair A goes from up to right; pair B goes from right to down. Both turn one quarter-turn clockwise. Their starting directions differ, but their relationship is the same.

Pair B also starts solid and has three dots. Those starting features do not make it different: its fill and dots stay unchanged within the pair, just as in A.

Level 1 compares turns. Level 2 adds a switch between solid and outline. Level 3 also moves one or two steps through the dot cycle 1 → 2 → 3 → 1. Compare each kind of change separately.

Four of these five pairs turn one quarter-turn clockwise while keeping the fill and dots unchanged. One pair uses a different turn. Is it C or E?

Read the first and second arrows inside each panel. An unusual starting direction, fill or dot count is not the criterion; the transformation is.

This checkpoint narrows the choice to two panels. In the practice, you choose from all five panels, with six questions in each round.