Stream of consciousness rationale: Flora has 50 * 2 = 100 books. Gary has 50 / 2 = 25 books. Together they own 100 + 25 + 50 = 175 books.
The question and answer pair are described below.
Q: Harry has 50 books in his library. His sister Flora has twice as many books and their cousin Gary has half the books Harry has. How many books do the three of them own together?
A: 175