RAS question
Two positions of a dice are shown: Position I: Top=3, Front=5, Right=2 Position II: Top=3, Front=4, Right=6 Which number is opposite to 5?
Correct answer: (C) 4.
The number opposite to 5 on the dice is 4.
Explanation
In both shown positions, the top face remains 3, so the dice has only been turned around the vertical top-bottom axis. NCERT's Class VII Mathematics exemplar treats a cube as a solid with flat surfaces called faces, which is the same face-relation idea used in dice questions. In Position I, the visible faces are 3 on top, 5 in front and 2 on the right. In Position II, with 3 still on top, the front face changes to 4 and the right face changes to 6. This rotation means the two front positions shown, 5 and 4, lie on opposite sides of the dice while sharing the same top reference face. Therefore, 4 is opposite to 5.
Why the other options are wrong
- (A) 2 is visible on the right face in Position I alongside 5, so it is adjacent to 5 rather than opposite to it.
- (B) 6 appears on the right face in Position II after rotation around the same top face, so it belongs to the side-face cycle, not the face opposite 5.
- (D) 1 is not shown in either given position, and the provided rotations already identify 4 as the face opposite 5.
Concept
This tests spatial reasoning with cube and dice face relations: using a fixed reference face to infer adjacency and opposition. It recurs in RAS because mental ability questions often ask candidates to visualise rotations without drawing the full cube.