Hello, sri340!

The problem seemed to have no unique solution . . . a silly problem.

Then I had a thought (always a dangerous event):

If the given answer-choices are theones available,only

. . then there is a solution . . . and the problem is even sillier!

The table above shows the number of consecutive nights that each

of five families stayed at a certain hotel during a 14-night period.

If the Sui family’s stay did not overlap with the Lisa family’s stay,

which of the 14 nights could be a night on which

only one of the five families stayed at the hotel?

. .

From the given clue, Sui's family and Lisa's family spanned the entire fortnight.

There are two possible scenarios.

Here's one of them:

. . . . . . . . . . . . . . .

Thomas' family covered 10 consecutive nights:

. . ranging from [1,10] to [5,14]

If Thomas stayed [1,10], [2,11], or [3,12]

. . all 5 answer choices are eliminated.

Hence, Thomas must have stayed [4,13] or [5,14].

Therefore, the night could have had only one family.

. . [So why tells us about Shawn or David?]