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Category: Kids (middle school and up)

Reflection on Billiards and Math Feb 2024

  • khoitsma
  • General, Kids (middle school and up), Mathematics
  • 0 Comments

This inscribed triangle is a periodic billiard trajectory called the Fagnano orbit, named for Giovanni Fagnano, who in 1775 showed that this triangle has the smallest perimeter of all inscribed triangles.

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What is the Day of the Week? Jan 2024

  • khoitsma
  • General, Kids (middle school and up), Mathematics, Mental Math
  • 0 Comments


odd months

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Engineering Math Nov 2023

  • khoitsma
  • Engineering, Kids (middle school and up), Mathematics, Mental Math
  • 0 Comments

“Often while working, an arithmetical answer is needed — exact is sometimes required, approximate is often acceptable — maybe the basis of a decision or a path forward is based on a few quick calculations, with more rigorous calculations to follow

Multiply by 11 (or 12). Just write down the answer !
Pascal’s Triangle
Aliquot Parts

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Buckminster would be proud Nov 2022

  • khoitsma
  • Concept, General, Kids (middle school and up)
  • 0 Comments

… maybe

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Rechnen, Multiplizieren und Addieren Nov 2022

  • khoitsma
  • Kids (middle school and up), Mathematics, Mental Math
  • 0 Comments

Sum the numbers — let me count the ways

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Weather Sep 2022

  • khoitsma
  • General, Kids (middle school and up), Science, Windy
  • 0 Comments

The Windy app has a beautiful interface


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