Not saying it's right or wrong, but the only that comes to mind is: Two Days in a Weekend. Although my students would disagree to that statement.
Personally I do not think this is it though, and shall think upon it some more. Any other thoughts?!
It can be
2 doors in a window.
What does 81 S in a S S P mean?
if the question were
81 S in a S P
the answer would be
81 Squares in a Sudoku Puzzle
so the extra S letter is a mystery
unless
81 Squares in a Standard Sudoku Puzzle
as there are other variations
i think it should be 9d in a ss / 9digit in a social security number?
What does the ditloid 25 P in the P - BRIT - mean?
25 Pounds in the Pony - Britain
*A pony is slang for a sum of 25 pounds. From the latter half of the eighteenth century, the word pony was used as slang for a sum of 25 pounds in the city of London, the capital of the United Kingdom.
What does 17 S H in the W mean?
1 7 Star Hotel In The World
The Clue is being read incorrectly.
17 S H in the World should read as
1 7 S H in the World; the number is not 17, but rather 1 and 7.
Snype