Two positions of a dice are shown below (i) and (ii). When 3 is at the top which number will be at the bottom?

Number three is common in both the figures we assume the block in figure (ii) to be rotated so that three appears at the same position as in figure (i) and the numbers 5 and 2 move to the faces hidden behind the numbers 4 and 6 respectively. Thus the combined figure will have 3 on right hand side face, 4 on the front face, 6 on the top face, 5 on the rear face and 2 on the bottom face. Clearly when 2 is at the bottom, then 6 is at the top.

15 × 3 + 13 × 2 + 11 × 1 = 82 cubes

There are 20 cubes.

There are total 42 cubes present in the upper portion.
Then total cubes be 42 × 2 = 84
Second method to find out the number of cubes/blocks.
24 columns with 2 cubes each = 24 × 2 = 48
14 columns with 2 cubes each = 28
4 columns with 2 cubes each = 8
Total cubes = 48 + 28 + 8 = 84

As per the given pattern in question figure , we can find the similar next position of given dice .
Yellow, Green, Blue and Violet are on the faces adjacent to Red colour.
Therefore, sixth colour is opposite to Red.
From the four views of cube, it is clear that yellow is opposite to Blue.

from figure i, ii and iv we conclude that 6, 4, 3 and 1 lie adjacent to 2. Hence 5 be opposite of 2.

For the better understanding take a dice ans apply the same steps which is mentioned above.

option (a) and option (d) will be eliminated as we see the figure as the pattern face is adjacent to face C, which cannot be possible. In Option (b) D and E both are adjacent to C, but there direction should be clock wise. Face D on the left side and face E on the right side that can be possible only when pattern face be on the top.

(a) satisfies all the conditions of dice formation or constructions.

in option (c) 2 and 5 are adjacent to the whiter portion side of the half shaded face, but in the option 2 is attached with the darker side, which cannot be possible.

b and c cannot satisfies the conditions of dice formation, as option (b) B cannot be adjacent to D and in option (c) two white faces cannot be adjacent to each other.