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A mathematician's way of converting miles to kilometers

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Re: A mathematician's way of converting miles to kilometers

#81

Post by Moru »

rocqua wrote: post #74
ghaff wrote: post #70

Earlier quoted context omitted.

That's fair enough. Whatever the advantages of Imperial in some narrow contexts, I'm not sure very many would argue for them absent legacy. On the other hand, it's pretty much an academic debate because a switch isn't happening for mainstream use. The desire and political will just aren't there. The little push that once existed is essentially gone whatever some tech types might want.

I like arguing for arcane standards, and there are aspects of the imperial system I like. Specifically, I tend to advocate for a base 12 system based arround the inch. Base 12 because the very structured multiplication table, which also makes for easy dividing. The inch because I find my lengtg estimation accuracy to be better captured by inches.

Your length estimation accuracy is dependent on what you used more.

Re: A mathematician's way of converting miles to kilometers

#84

Post by zonidjan »

magoon wrote: post #73

I use a similar method of easy-to-remember numbers in conversion between celsius to Fahrenheit: 0 = 32 10 = 50 20 = 68 30 = 86 Then roughly, subtract/add two F for every extra C. It’s easy to remember 32 and 50, while 68 and 86 are reversed.

Meh. Every 10F difference is a bit under 5C difference (since the ratio is 9:5). So you can estimate that 40F~5C, 50F=10C, 60F~15C, etc. All I remember is 2:1 and 32F=0C.

Re: A mathematician's way of converting miles to kilometers

#86

Post by ghaff »

rocqua wrote: post #74
ghaff wrote: post #70

Earlier quoted context omitted.

That's fair enough. Whatever the advantages of Imperial in some narrow contexts, I'm not sure very many would argue for them absent legacy. On the other hand, it's pretty much an academic debate because a switch isn't happening for mainstream use. The desire and political will just aren't there. The little push that once existed is essentially gone whatever some tech types might want.

I like arguing for arcane standards, and there are aspects of the imperial system I like. Specifically, I tend to advocate for a base 12 system based arround the inch. Base 12 because the very structured multiplication table, which also makes for easy dividing. The inch because I find my lengtg estimation accuracy to be better captured by inches.

I assume that 12 inches to a foot is the reason that, at least when I was growing up, we were taught multiplication tables up to 12x12 rather than 10x10.

Re: A mathematician's way of converting miles to kilometers

#87

Post by greggyb »

magoon wrote: post #73

I use a similar method of easy-to-remember numbers in conversion between celsius to Fahrenheit: 0 = 32 10 = 50 20 = 68 30 = 86 Then roughly, subtract/add two F for every extra C. It’s easy to remember 32 and 50, while 68 and 86 are reversed.

I find it helpful to do similar, but mine is fuzzier and tied to day-to-day activities. I am a gross farenheit user, so this is my mental table for cross reference

    -42|-42: 9th layer of hell
    0|32: freezing point
    10-15: maybe think about a jacket
    20-25: room temp
    37|98: body temp
    50: death valley
    100|212: boiling
It's not precise, except for some intersection points, but it sticks well for me and allows me to be conversational enough to impress metric-folks when I convert my temps to rough Celsius for them. It's rare to need precise temp in conversation.

Re: A mathematician's way of converting miles to kilometers

#90

Post by regularfry »

nesadi wrote: post #25
ghaff wrote: post #14

Earlier quoted context omitted.

There are a fair number of people who seem to take personal offense that the US (and to some degree the UK) don't use SI for everyday types of things and add it to their laundry list of grievances about the US generally. Never mind the fact that SI is generally used for engineering and other areas where it has legitimate advantages (which miles vs. kilometers doesn't really in day-to-day life).

> that SI is generally used for engineering Except when it isn't? Are you telling me SI is used in engineering everywhere in the US? I've heard too many stories (especially accidents) to believe that in any way.

On the UK railways, I think I'm right in saying that the only place imperial units are used is in measuring the curvature of track, which involves chains.
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