Step 1: Treat each couple as a block.
If each husband must sit next to his wife, consider each couple as a single block. There are $3$ blocks to arrange around a circle. For circular arrangements (only rotations considered identical), the number of ways to arrange $3$ distinct blocks is $(3-1)! = 2$.
Step 2: Arrange within each block.
Inside a couple's block, the two people can sit as $(H,W)$ or $(W,H)$, i.e., $2$ ways per block.
Hence internal arrangements contribute a factor of $2^3 = 8$.
Step 3: Multiply choices.
Total valid seatings $= (3-1)! \times 2^3 = 2 \times 8 = 16$.
\[
\boxed{16}
\]
How many possible words can be created from the letters R, A, N, D (with repetition)?
Let R = {(1, 2), (2, 3), (3, 3)} be a relation defined on the set \( \{1, 2, 3, 4\} \). Then the minimum number of elements needed to be added in \( R \) so that \( R \) becomes an equivalence relation, is:}
The figures, I, II, and III are parts of a sequence. Which one of the following options comes next in the sequence as IV?
For the beam and loading shown in the figure, the second derivative of the deflection curve of the beam at the mid-point of AC is given by \( \frac{\alpha M_0}{8EI} \). The value of \( \alpha \) is ........ (rounded off to the nearest integer).