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TED-Ed Original lessons feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed original? Nominate yourself here »

Meet The Creators

  • Educator Daniel Griller
  • Script Editor Alex Gendler
  • Director Patrick Smith
  • Animator Patrick Smith
  • Associate Producer Elizabeth Cox, Jessica Ruby
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Narrator Addison Anderson


Additional Resources for you to Explore
This riddle is an adaptation of “Helen on the island” and appears in its original form in the book Elastic Numbers: 108 Puzzles for the Serious Problem Solver by the educator. The problems in the collection require minimal technical knowledge but vary enormously in difficulty. It is highly recommended for anyone who enjoys a challenge!