[HKMk23]

“1/3 of a half-meter is...” 6-9/16 inches. For all practical intents and purposes.

[Svartalfiar]

“1/3 of a half-meter is...” 6-9/16 inches. For all practical intents and purposes.

And to my point, a useless number. Converting it to regular units doesn't help you actually do the math in metric.

Metric is fine if you want to divide by two or ten (fifths isn't a oft-used divisor), but the very commonly used third or quarter isn't very smooth in metric. But a base-12 system of feet and inches easily handles halves, thirds, quarters, and tenths.