Thinking Skills
Four identical square tiles are placed in a 2×2 grid. Some tiles are rotated before placing. The finished 4×4…
Question 1 · Multiple choice
Question
Four identical square tiles are placed in a 2×2 grid. Some tiles are rotated before placing. The finished 4×4 pattern of cells looks like this (○ = white, ● = black):
○ ● ● ○
● ○ ○ ●
● ○ ○ ●
○ ● ● ○
Each tile is 2×2 (4 cells). Which description matches the design on each tile?
Options
- A.All 4 cells are the same colour.
- B.The top row is black and the bottom row is white.
- C.Two diagonally opposite cells are black and the other two are white — a 2×2 checkerboard.
- D.Only one corner cell is black; the rest are white.
Correct answer
Explanation
Step 1: Split the 4×4 pattern into four 2×2 tiles.
The full pattern is:
○ ● ● ○
● ○ ○ ●
● ○ ○ ●
○ ● ● ○
Label the four tiles by their position:
[Tile A] [Tile B]
[Tile C] [Tile D]
Step 2: Read off each tile.
Tile A (rows 1–2, columns 1–2):
○ ●
● ○
Top-left = white, top-right = black, bottom-left = black, bottom-right = white. The two diagonally opposite cells (top-left and bottom-right) are white. The other two diagonally opposite cells (top-right and bottom-left) are black. → This is a checkerboard pattern. ✓
Tile B (rows 1–2, columns 3–4):
● ○
○ ●
Top-left and bottom-right = black. Top-right and bottom-left = white. → Same checkerboard, just rotated 90°. ✓
Tiles C and D (bottom half) follow the same pattern in the same way. ✓
Step 3: Identify the correct description.
All four tiles share the same design: two diagonally opposite cells are black, and the other two are white — which is exactly a 2×2 checkerboard.
Option C describes the tile correctly.




