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A comment on What’s Wrong with “Multiplication Is Repeated Addition”? (2008). Parent comment

Re:What’s Wrong with “Multiplication Is Repeated Addition”? ... by np_tedious on Wednesday March 03, 2021 @09:55AM (#26329102)
Still don't see the difference.

Density times volume is mass. Volume times density is mass. Distance times force is work/energy...

"5 times I will connect 12 apples"

[ Parent | on HN ]
Re:What’s Wrong with “Multiplication Is Repeated Addition”? ... by KMag on Wednesday March 03, 2021 @10:16AM (#26329385)
You're correct. The GP in incorrect about their dimensional analysis. 5 apples 12 times yields apples because it's apples times a dimensionless scalar (count). Newtons times meters is always Newton-meters, never Newtons or meters. Units are never magically dropped in dimensional analysis.
[ Parent | on HN ]