Question

Two positions of a parallelepiped are shown below. When the number $3$ will be on the top side, then which number will be at the bottom?

• A. $1$
• B. $4$
• C. $5$
• D. $6$

Answer 1

Answer: (C)

$5$

The number $2$ is common to both the figures. We assume the parallelepiped in fig. (ii) to be rotated so that $2$ appears at the same position as in fig. (i) i.e. on the RHS face and the numbers $6$ and $3$ move to the faces hidden behind the numbers $1$ and $5$ respectively [in fig. (i)]. Then, the combined figure will have $1$ opposite $6$ and $5$ opposite $3$. Thus, when $3$ will be on the top, then $5$ will appear at the bottom.