What is the Day of the Week? Jan 2024

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

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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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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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On Average Jun 2022

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

Most everyone in math knows these tricks — here’s a summary of techniques used to make quick mental calculations of averages.

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Lucky Me Jun 2022

• khoitsma
• Computer Algebra, General, Mathematics, Mental Math, Personal, Python, Software
• 0 Comments

As a kid and later through my career, several lucky things happened to me; some of these things were fortuitous and some happened because I searched them out — either way, still lucky.

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