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Daniel M. Oppenheimer: 2 puzzles worth knowing

2 puzzles from Daniel M. Oppenheimer, each explained in a minute and credited to the original work. Free on Savvy.

• Emily's father has three daughters — name the third one

  Emily's father has three daughters. The first is named April, the second is named May. What is the third daughter's name?

  — Keela Thomson and Daniel Oppenheimer, Investigating an Alternate Form of the Cognitive Reflection Test

• You overtake the runner in second place — what place are you in now?

  You're running a race and you pass the person currently in second place. What position are you in now?

  — Keela S. Thomson and Daniel M. Oppenheimer, Investigating an Alternate Form of the Cognitive Reflection Test

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