Actually you are misinterpreting the formula,
1 (larger units, feet in this case) * 12 (conversion factor between feet and inchs) = 12 (smaller units, inches in this case)

Likewise, 24 (smaller units) / 12 (conversion factor between feet and inches) = 2 (larger units)

Likewise, 2 (larger units) * 100 (conversion factor between centimeters and meters) = 200 (smaller units)


The conversion factor is not the how. The how is the formula and the conversion factor is a variable dependent on the unit types involved in the conversion.

Sure magnitudes of ten are neat, but has only two very minor advantages (too small to worry about in my opinion), first is easier to memorize the common conversion factors (by the age of adulthood this has long since passed being an issue for one's native measures) and two is when frequently converting. It also has the disadvantage of making unit conversion mistakes harder to find, particularly in larger equations where the difference between two units is often nothing more than a 0.

Imperial units

1 foot = 12 inches
1 cubit = 1.5 feet = 18 inches
1 yard = 2 cubits = 3 feet = 36 inches
1 chain = 22 yards = 44 cubits = 66 feet = 792 inches
1 furlong = 10 chains = 220 yards = 440 cubits = 660 feet = 7,920 inches
1 mile = 8 furlongs = 80 chains = 1,760 yards = 3,520 cubits = 5,280 feet = 63,360 inches
1 league = 3 miles = 24 furlongs = 240 chains = 5,280 yards = 10,560 cubits = 15,840 feet = 190,080 inches

Gosh, it seems like someone already said that.

Gosh, a half-dozen people posted whilst I was typing.

There's some other good stuff here:

http://mentalfloss.com/article...g-sense-measurements

I think that if the OP had asked Google their question, rather that us, they'd have gotten their answer a lot sooner and without rancor.

In reply to Alyse (msg # 70):

lol, happens to me all the time, too :-)


In reply to Arkyn (msg # 71):

Everything's better with rancor.  http://starwars.wikia.com/wiki/Rancor

Touche', Cruinne.

In reply to Arkyn (msg # 73):

Omg! I posted this question once i logged and saw my games all black. I Remeber I was at the toilette too LOL.

What have I done !!! ???

I just remember that 1 inch is approximately 2.54 centimetres and it's all downhill from there. ;>

As a personal preference, I like imperial measurements for fantasy games, and metric for SF.  Just feels right.

What really confuses players IRL is when you say "you can move inch on the map," and they look at me like I just threw poop at them. So not even Americans can look at something and say "hey thats a foot."

I'm British and generally what I use depends on what I'm measuring.

I measure peoples' heights in feet and inches and body measurements in inches (ie 36-30-34)

I say "a few feet away" or "[X] feet tall" is something is not very far/ big. (If your character is 5'8" then it's easy to relate to an object being 8' tall).

If it's larger I might say "100 metres" or "2 kilometres".

I measure speed and the distance between locations in miles per hour and miles because that's how our road signage works.

I measure weights and fluids in metric: 100grams, half a kilo, 2 litres, etc. Because that's how our foodstuffs are sold.

But I have no clue when it comes to how much characters weigh. It doesn't matter whether you use metric or imperial I have absolutely no frame of reference for that.

In reply to Undeadbob (msg # 76):

This depends, as one with experience in carpentry, I can look at something and judge feet/inches. The interesting thing I found is that accuracy drops off beyond 3-5 units regardless of unit size.

In reply to DarkLightHitomi (msg # 78):

Its a difficult skill to master, I only have it because of martial arts practice lol. Course its probably because my players IRL are always noobs, since no one wants to stick around and listen to me talk for 8 hours.

What kind of martial arts practice has you moving an inch on the map?

Ah no you misunderstand, martial arts allows me to know distances between me and a person. Not very many people can understand that, without some sort of practice at, not saying I'm awesome at it or anything.

You're lucky. I found that it was the complete opposite, for me, going from training to "real" fights. Totally unprepared for the way stress hormones distort apparent distance and size. I read somewhere that the shape of the eye literally changes, but I don't know if I believe that.

My spatial recognition and hand-eye coordination were totally screwed up.

Talking to my instructor, he said that you can eventually learn to compensate, but the only way is to put yourself in "real" stress situations.

Not worth it, imho, but it gave me a new perspective on running games. Characters are definitely in stressful situations just walking down a corridor. Their senses won't be accurate, so I don't sweat giving them accurate descriptions; just ones that are atmospheric and emotionally infused.

Stopped using minis and maps for just that reason; it's not immersive enough unless the character is literally a walking battlefield computer. Situational awareness just doesn't work that way.
This message was last edited by the user at 16:17, Fri 31 Oct 2014.

In reply to Tortuga (msg # 82):

Yes that does make perfect sense, I just use 3D paper terrain deals now. Much more immersive than a hex grid, but it takes time and money so I've started small. Also heroclix are super cheap on the Internets and easy to pop of the base to be glued on penny or piece of card board..

I wish we learned Metric in US early on, because most sciences use metric, but I only have a feel of how tall/cold/heavy something is in imperial units because that's what I grew up with :( , so just an additional hurdle in learning science things.

The how is the formula that converts inches to feet.
It is simple:
12 inches = 1 foot
xx inches = ?
so ? is xx/12

Is 12 a variable? No, it a part of the formula that is constant and we cannot convert to foot without it. Because, again, if it would be no different from the metric system, we could use a 10.


In the meantime children using metric system can go shopping without fearing to be cheated then?


I suppose you are talking about the units in the same metric system. If that is so, the system is designed to be fool-proof, unless you are talking about a very obscure and rare case.

It is a variable, same formula but 12 is replaced by other numbers when converting different units, I.E. 12 is replaced by 100 when converting centimeters to meters, thus 12 is a variable dependent upon the units being converted rather than other numbers, but that doesn't make it any less a variable.


Honestly, mathematical skill isn't even involved in this issue. Besides adults aren't any better at avoiding being cheated then kids.

Besides, how does metric play into shopping?



Metric isn't fool-proof, you still use formulas to convert units, the same as any other system.

However, a number being off is easier to spot when the numbers don't end in 0. I.E. 12 * 12 = 144, but by accident you put 12 * 1 = 12 is easier to spot than 10 * 10 = 100 ends up by accident as 10 * 1 = 10.

144 vs 12
100 vs 10
Which has the easier to notice difference? Seems small here but just drop that into a pageful of numbers and see how easy it stays.

It can... Where I live produce and meat are sometimes marked in per-pound prices, and sometimes marked in per-kilo prices, and sometimes marked in per-hundred-grams prices.  You have to be pretty aware though because all the supermarkets write the price numbers quite large and the unit quite small.

What might seem like a bargain or even a reasonable when you normally think of it in kilos can be a total rip-off if that's actually the per-pound price (and you were distracted and just picked up a bag of it and went on your way).

I sometimes wonder if it happens as much to others as to me, or I'm just particularly out in la-la land when I have to go to the store but at least once a month or so I take some fruit to the counter only to be hit with severe sticker shock and have to go "Uh, no, I do not want to pay $26 for that bag of cherries, thankyouverymuch."

Anyway... must be extra confusing for a generation that didn't grow up steeped in pounds.
This message was last edited by the user at 16:33, Thu 06 Nov 2014.

Which, of course, means that Laditis is right. 12 is not a variable when converting inches to feet. Also 12 is not 10, so the how is different than converting centimeters to meters, because as you have said the 12 is replaced by a 100 in the formula, making the formula different.


You brought the issue.


You said metric is easier to memorize. Therefore imperial is harder to learn. You said by the age of adulthood, it is has not been an issue for a long time. I have to think that it is a problem by childhood to at least preadolescence.

Food is weighted in kilos, fabric is measured in meters, candies are weighted. But chldren worries mostly about candies.



100 has more digits than 10, so I have an easier way to spot that someone multiplied 10 * 1 instead of 10 * 10. In any case, we can just use a bigger unit and solve the problem. Maybe I misunderstood your concern?

Laditis, let's take our distance from this discussion. I guess maths work different in different countries.

A formula has variables, some variables depend on another number, while other variables depend on other types of things.

In the conversion formula one number depends on what is being converted, another number depends on how much is being converted, the last number is dependent on the other two. As long as you know two of those numbers (regardless of which two), the third number can be determined, hence all three numbers are variables.

The how doesn't care about the details, all steel boats float by the same mechanics, yet each boat is different. How they float is the same regardless of the details of their construction.

The "how" in "how units are converted," is the same, no matter how those units may be defined.

Yep, totally different.