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Twins born in different years

calendarlateral-thinkingtime-zones

Ana and Ben are twins. Ana was born first, and Ben followed just five minutes later. Yet their birth certificates show birthdays in different years.

  1. How is that possible?
  2. In another family, twins are born a few minutes apart, but the twin born second has the earlier official birth date. Explain how that can happen.
Show a hint

Think about what happens to the date at midnight, and about what happens to the clock when you cross a time-zone line or when daylight saving time ends.

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