Pointing to a photograph of a young girl, Sarah remarks: 'Her mother is my mother's only daughter.' If Sarah is looking at a photograph of someone else, what is the girl's relationship to Sarah?
Sarah's daughter.
'My mother's only daughter' refers to Sarah herself. Therefore, 'Her mother is Sarah,' meaning the girl in the photograph is Sarah's daughter.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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