I agree with Michell that bringing the metric system into discussions of ancient measures can be problematic, but since I am comparing and contrasting the remen and royal cubit to the metric system as meridian measures...
Schwaller de Lubicz believed that the length of the meter was known and used in ancient Egypt, and that the meter is related to the cubit by number. phi sq/5 = pi/6 = .5236 = the relation between the meter and the royal cubit. Alternatively, 11/21 = .5238 = the relation between the meter and the royal cubit, and since the meter is a tiny bit shorter than it is supposed to be as a meridian measure, .5238 actually works better for the length of the royal cubit and the remen as meridian measures, in relation to the meter. Several years ago I posted a webpage about this. Here is the link:
Note to PB: the first picture may have some relevance to the Michaelmas thread.
Here is a submission guideline from JAEA that is typical for ancient Egyptian journals: "Use metric units and the SI system wherever possible. Provide metric translations if values must by expressed in other units, such as when quoting from publications using dimensions like 20 feet (6.09m)." Michell did not use the internet or email either, and who could blame him. But, the times are what they are.
PS: Here is a picture of the inside cover of my copy of Ancient Metrology: