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Comment by zwarag | Hacker News Reader

22000 foot are 6705.6 meters.

Although beware excessive precision: https://blog.plover.com/physics/precision.html

Maybe 6700 meters, to match the 2 digits of precision.

Although from the article: "he encountered another yellow-rumped mouse even higher than previously sighted, atop the very summit of Llullaillaco, at 22,110 feet" -> 6739 meters

I feel like this is still an unsolved notational problem. Let's say I want to give you the elevation of Mt Everest in feet to 3 sig figs. I could say 29,000 ft, but that'd be misread as 2 sig figs. So I have to say something like 29010^2 , or 2.9010^4 , to convey the correct information. Or just 2.90e4. Maybe there's nothing better?

Famously, the original surveyor of Mt Everest calculated 29,000 exactly but lied and added 2 feet to make it 29,002 so that people would understand he meant 5 sig figs, not just 2. That's one way of solving the problem ...

It's easy enough to invent a notation, like

    29,0·00

Maybe this new standard notation was born today on HN!

The usual way is a line. It can be faked here with code formatting (4 spaces to force mono font) and underscores:

    ___
    29000

It bothers me that this overloads the notation for repeating fractions. I guess there wouldn't be a use case requiring both in a single number, but you can imagine multiple numbers on the same page using this formatting for different purposes and it being confusing.

And it's fine for writing out by hand or in TeX (I assume), but good luck using it in any other context as we see here! Ideally a notation would be keyboard-friendly, at least for something with as wide an applicability as this anyway.

But this is certainly a good starting point.

> multiple numbers on the same page using this formatting for different purposes and it being confusing.

I think it's unambigous at least: 2̅9̅0̅00 vs 11̅.̅4̅2̅8̅5̅7̅; sigfigs has overline at the start, while repeating has overline at the end.

> "[...] atop the very summit of Llullaillaco, at 22,110 feet" -> 6739 meters

That's exactly the elevation listed in the Wikipedia article too: https://en.wikipedia.org/wiki/Llullaillaco

As a former physics teacher this reply gave me a warm fuzzy feeling.

If the height is exact 6700, they will usually add some random number, otherwise people wouldn't believe it is 6700...

what he did was fine as it's an exact conversion 1 inch = exactly 2.54 cm and you can go from there.

And -75F is -60C. Mind blowing. Even a human would have a problems surviving that. How could survive mouse body having a much bigger surface area to a volume ratio? Heat insulated nests maybe?

> temperatures sometimes plunge below minus 75 degrees Fahrenheit.

Sometimes. And the mice are usually hibernating during that time.

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