I’ll also defend fractional measurements over decimal to my dying breath. Decimal measurements can’t express precision very well at all. You can only increase or decrease precision by a power of 10.
If your measurement is precise to a quarter of a unit, how do you express that in decimal? “.25” is implying that your measurement is precise to 1/100th - misrepresenting precision by a factor of 25.
Meanwhile with fractions it’s easy. 1/4. Oh, your measurement of 1/4 meter is actually super duper precise? Great! Just don’t reduce the fraction.
928/3712 is the same number as 1/4 or .25, but now you know exactly how precise the measurement is. Whereas with a decimal measurement you either have to say it’s precise to 1/1000th (0.250), which is massively understating the precision, or 1/10000th (0.2500), which is massively overstating it.
No measured value will be perfectly precise, so it doesn’t make sense to use that as a criteria for a system of measurement. You’re never going to be able to cut a board to exactly 1/3 of a foot, so it doesn’t matter that the metric value will be rounded a bit.
i’ve never heard of anyone using non-reduced fractions to measure precision. if you go into a machine shop and ask for a part to be milled to 16/64”, they will ask you what precision you need, they would never assume that means 16/64”±1/128”.
if you need custom precision in any case, you can always specify that by hand, fractional or decimal.
But you can’t specify it with decimal. That’s my point. How do you tell the machine operator it needs to be precise to the 64th in decimal? “0.015625” implies precision over 15,000x as precise as 1/64th. The difference between 1/10 and 1/100 is massive, and decimal has no way of expressing it with significant figures.
I’ll also defend fractional measurements over decimal to my dying breath. Decimal measurements can’t express precision very well at all. You can only increase or decrease precision by a power of 10.
If your measurement is precise to a quarter of a unit, how do you express that in decimal? “.25” is implying that your measurement is precise to 1/100th - misrepresenting precision by a factor of 25.
Meanwhile with fractions it’s easy. 1/4. Oh, your measurement of 1/4 meter is actually super duper precise? Great! Just don’t reduce the fraction.
928/3712 is the same number as 1/4 or .25, but now you know exactly how precise the measurement is. Whereas with a decimal measurement you either have to say it’s precise to 1/1000th (0.250), which is massively understating the precision, or 1/10000th (0.2500), which is massively overstating it.
Fractional measurements are awesome.
No measured value will be perfectly precise, so it doesn’t make sense to use that as a criteria for a system of measurement. You’re never going to be able to cut a board to exactly 1/3 of a foot, so it doesn’t matter that the metric value will be rounded a bit.
Not “a bit”. You can have a 9x difference in precision and be unable to record it.
i’ve never heard of anyone using non-reduced fractions to measure precision. if you go into a machine shop and ask for a part to be milled to 16/64”, they will ask you what precision you need, they would never assume that means 16/64”±1/128”.
if you need custom precision in any case, you can always specify that by hand, fractional or decimal.
But you can’t specify it with decimal. That’s my point. How do you tell the machine operator it needs to be precise to the 64th in decimal? “0.015625” implies precision over 15,000x as precise as 1/64th. The difference between 1/10 and 1/100 is massive, and decimal has no way of expressing it with significant figures.
I’m scratching my head, wondering why all the downvotes.
I’ve always sucked at math tbh, but fractional measurements are my jam. It goes faster in my head and I can visualize things better.