As we all know Dice is a part of the one of our popular indoor game since immemorial times. Presently, it is one of the interesting chapters of Reasoning and also included in the syllabus of RRB & SSC JE exams. Now, let us discuss, dice is a three-dimensional figure in which there are 6 Surfaces, 12 Edges and 8 Corners. There are 4 adjacent surfaces to each surface.
Here, ‘=’ represents Edges
‘→’ represents Surfaces
and, ‘●’ represents Corners
In exams two or more positions of a dice are given in a question and your task is to find out the opposite surface of a given surface.
Example:
From the above two positions of a dice it is clear that 2,3,4 and 5 are the adjacent surfaces of surface ‘1’. Therefore, we can say that opposite surface of ‘1’ is surface ‘6’.
- TYPES OF DICE
I. STANDARD DICE: The dice in which the sum of two opposite surfaces is
equal to seven is considered as Standard Dice.
For Example:
In the above dice, 5,3 and 1 are adjacent surfaces and it is clear that the sum of any two surfaces shown in dice is not equal to seven.
Therefore, Surface opposite to ‘5’ is Surface ‘2’ (i.e 5+2=7)
Surface opposite to ‘3’ is Surface ‘4’ (i.e 3+4=7)
Surface opposite to ‘1’ is Surface ‘6’ (i.e 1+6=7)
II. GENERAL DICE: In General Dice the sum of two opposite surfaces is not equal to seven. To find out the opposite surface we are required atleast two positions of dice having:
(a) one surface common
Here, Surface ‘3’ is common surface in both the positions of dice. After fixing ‘3’ and then moving in clockwise direction we can easily find the opposite surfaces.
3 – 6 – 4
3 – 5 – 2
It is clear that 6 and 5 are opposite surfaces and, 4 and 2 are opposite surfaces. Therefore, surface opposite of surface ‘3’ is surface ‘1’.
(b) Two surface common
In the above two positions of dice, two surfaces i.e Surface ‘3’ and Surface ‘2’ are common.
3 – 2 – 1
3 – 2 – 6
After fixing surfaces 3 and 2, we find that surface opposite of surface ‘1’ is surface ‘6’.
Surface opposite of surface ‘3’ is not confirm, it may be surface ‘4’ or surface ‘5’. Similarly, surface opposite of surface ‘2’ is not confirm, it may be surface ‘5’ or surface ‘ 4’.
III. OPEN DICE: In open dice all the six surfaces are clearly shown. The opposite surfaces are at the alternate positions of rows or columns. For Example:
Here, opposite of surface ‘1’ is surface ‘4’
opposite of surface ‘3’ is surface ‘5
opposite of surface ‘2’ is surface ‘6’
- EXPANSION OF DICE: In expansion of dice we are given two or more positions of dice and we have to represent all the six surfaces in open dice.
For Example:
In the above two positions of dice common surface is ‘4’.
Always fix the common surface at the centre position.
From first position:
i.e
From second position:
i.e 
Clearly blank surface will be filled by remaining number i.e ‘6’
Therefore, opposite surfaces are: 1↔ 2, 4 ↔ 6 and 3 ↔ 5
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