Unit 13 · Spatial Reasoning
Grey Mat Tiles — Find the Hidden Pattern
Lesson 1 of 2
Visual tile and rotation questions are among the most satisfying in OC TS Spatial Reasoning — because once you identify the single tile that builds the whole design and understand its rotation rule, the hidden region writes itself. Let's delve right into this type.
Tile rotation and hidden-pattern questions appear consistently in OC TS and are near-certain marks for students who approach them methodically. The question always comes down to the same insight: if a design is built from four identical tiles each rotated 90°, every cell in the hidden area can be deduced from the visible cells of the matching tile.
The examiner wants to know whether you can identify the single base tile, trace how it is rotated into each of the four positions, and then use the rotated version to predict what symbols are hidden under the covered area — cell by cell — without guessing.
A 2D design is assembled from four identical tiles, each rotated 90° clockwise from the previous. A grey mat or cover hides the central portion of the design, which contains exactly one corner from each tile. You are given four answer options (A–D), each showing a different possibility for what is under the mat.
Best approach: Pick one clearly visible tile and note the symbol in each of its four cells. Then mentally rotate that tile 90° clockwise to match the orientation of the tile whose hidden corner you are deducing. Read off the symbol at the relevant position. Repeat for each of the four hidden cells. Then eliminate answer options one by one — any option that contradicts even one of your deduced symbols is wrong.
Question
Jimmy made a design using four identical tiles. His mother put a grey colour mat in the middle of the design as shown below.
Which option correctly shows what is hidden under the grey mat?
Select an answer to see the explanation.
Give Your Child the Best Chance at OC Entry
Join NSW families preparing their children for the Opportunity Class Placement Test with the most realistic online OC practice tests available. First tests free—no credit card required.
Claim Your Free OC Practice Tests