SSC CGL Reasoning · Dice and Cubes
Opposite Faces of a Dice
Find the face opposite a given face from two or three views of the same dice, using the fact that a face touches four others and is opposite the one it never meets, or from a flat net of the cube.
Why this matters
Forty-one questions in the bank, 16 from the 2023 shifts and 25 from the 2024 shifts, with 23 EASY and 18 MODERATE. Nearly all fall to one rule about neighbours, which needs only a list of the faces seen together.
Concept 1 of 2: The face that never appears beside it
Definition
1. For each view, write the three faces it shows. Any two of them are neighbours, never opposite. 2. Pick the face the question asks about (or one that appears in many views) and list all its neighbours. 3. When four different neighbours are listed, the sixth face is opposite it. 4. If you have fewer than four, find another face's opposite first and remove that pair.
- Fast route: start with the face that appears in the most views. It usually has four known neighbours at once.
Worked example
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
Example 1 · Dice and Cubes · Opposite Faces of a Dice
Choosing a face from the same view
Stopping at three neighbours
Assuming opposite faces add to 7
Concept 2 of 2: Opposite faces in a net
Definition
- In a straight row or column of squares, alternate squares are opposite: in a row of four A, B, C, D, A is opposite C and B is opposite D.
- Two squares joined on one side of the row (one above, one below) are opposite each other when they are separated by the row.
- Squares that share an edge in the net are never opposite.
- Fast route: find the longest straight line of squares and pair its alternate squares; the two squares left over are the last pair.
Worked example
Practice this conceptself-check · 4 quick reps
The same idea in a real exam question:
Example 2 · Dice and Cubes · Opposite Faces of a Dice
Pairing neighbours in the net
Counting two apart around a corner
Summary — formulas & gotchas at a glance
A revision cheat-sheet for the formulas and gotchas above. Click any concept name to jump back to its full explanation.
Watch out for (5)
- Choosing a face from the same view→ The face that never appears beside it
- Stopping at three neighbours→ The face that never appears beside it
- Assuming opposite faces add to 7→ The face that never appears beside it
- Pairing neighbours in the net→ Opposite faces in a net
- Counting two apart around a corner→ Opposite faces in a net
Test yourself on Dice and Cubes
20 past SSC CGL questions from this chapter, timed at 12 minutes and marked the way the exam marks it. You see your score and every answer the moment you finish. Free to start.