A line of 10 people is waiting in single file. Every person in an odd-numbered position (1st, 3rd, 5th, etc.) is wearing a coat. Every person in a position divisible by 3 is wearing a hat. How many people in line are wearing both a coat and a hat?
2 people
Positions divisible by 3 are 3, 6, and 9. Among these, the odd-numbered positions are 3 and 9. Thus, only the 3rd and 9th people fulfill both conditions.
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: Easy. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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