Obviously, if you have a foot, it's going to be a bit tricky to divide a metre into thirds. But if you have a metric tape it doesn't take much effort to "do the math" and meassure off 333mm.
Remember, a metre ISN'T divided into 10 sub units. It's divided into 1000 sub units. Read my earlier post to discover the subtle difference that this makes when it comes to dividing.
And we both know that real life doesn't always give round numbers, whether you're working in feet/inches or in millimetres. Personally, I'd much rather divide a four digit number by 3 (or any other interger) and round it off to the nearest millimetre in my head than muck about with all those fractions to get it to the nearest 16th inch.
I have no objection to using a base 12 system. I can see the logic of that. But why isn't applied consistantly ?
If there are 12 inches in a foot why isn't the inch divided into 12ths rather than 16ths ?
If a 12th of an inch is still too big why not 24ths ?
Why not have 12 feet in a yard ?
Wouldn't a 12oz pound and a 12 pound stone make sense ?
How about a 12 pint gallon ?
And that's one of the main draw backs of the whole imperial (or whatever you want to call it) system. There is no way of knowing whether you should be working is base 2,3,4,8,12,14,16,20 or something completely different unless you've had it beaten into you at school from a young age.
There are just too many units, each with a different name, that do almost exactly the same job.
If the foot and yard are so great why bother with rods, chains, perches and furlongs ? All that just to avoid "huge" numbers above 100 ?
Beyond that level. I just don't think fractions are that relavent on a day to day basis.
Besides, I think that you are too comfortable with only seeing certain demoninators in frations.
Does it really need to be a 1/12 ? Wouldn't 1/10 do the job just as well ?.
Why not use 1/20 instead of 1/16 ?
And of course, 1000/20=50. Which brings us back to my post of 23rd February.
Metric really works well when you're dealing with multiples of 50 and round numbers. It's immediately obvious how 150g or 450g or 700g relates as a proportion of a Kilo. You just don't need to use fractions in these instances.
Finally, I like your banana example. Personally, I'd buy "three" bananas if that's how many I wanted.
Anyway, why do you guys always pull the cheap trick of taking an imperial measure and converting it into metric to get a silly number so that you can use it in an improbable example ? Nobody is going to ask for 0.227 kg or even 227g of anything. They are going to ask for 250g. Hell, you could even ask for 1/4 Kilo if you wanted.