Detective Rossi was investigating a poisoning at a dinner party. The victim drank iced tea laced with arsenic. The host swore nobody touched the pitcher except him. Rossi noticed ice cubes floating in the victim's glass, but the pitcher of tea sitting on the warm table had completely melted ice cubes. Rossi arrested the host immediately. Why?
Ice melts faster in a glass than in a pitcher, or the ice in the glass was added after the tea was poured.
If the ice in the pitcher melted completely, the ice in the individual glass—which was poured earlier—should have melted even more. The presence of solid, unmated ice cubes in the victim's glass proved fresh ice was added to their drink long after the pitcher was served.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Hard. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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