There are 12 steamers plying between A and B.

Given: 12 steamers plying between A and B.

To find: number of ways the round trip from A can be made.

(i) The steamer which will go from A to B will be returning back, since the given condition is that same steamer should return.

There are 12 steamers available so there are 12 different ways to make around trip between $A \& B$ if done on same steamer.

(ii) If the return trip is done on different steamer than the once used in trip on going from $A$ to $B$ then the possible number of ways are: $12 \times 11=132$.

(11 because the once used in going from $A$ to $B$ cannot be used in returning hence, reduced by 1 .)