Sign up to save your library
With an OverDrive account, you can save your favorite libraries for at-a-glance information about availability. Find out more about OverDrive accounts.
Share
Find this title in Libby, the library reading app by OverDrive.
Search for a digital library with this title
Title found at these libraries:
| Library Name | Distance |
|---|---|
| Loading... |
Each cross has 4 triangles.You can rotate crosses around the axes.You can swap crosses.Task:All triangles on the bottom row must have different colors.All triangles on the top row must have different colors.All triangles in the central row on the right sides of the crosses must have different colors.All triangles in the central row on the left sides of the crosses must have different colors.All triangles in the columns follow the same rules.All triangles between crosses must have different colors.
Share
