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Xyzzy 2007-03-08 11:59

[quote]How did the Babylonians (or whoever) represent their 60 digits?[/quote]
We're assuming this is not a rhetorical question:

[url]http://en.wikipedia.org/wiki/Babylonian_number_system[/url]

S485122 2007-03-08 12:04

[QUOTE=davieddy;100222]How did the Babylonians (or whoever) represent their 60 digits?[/QUOTE]They used a mixture of base 10 and base 60, alternating both :
1, 10, 60, 600 (10*60), 3 600 (60*60), 36 000 (10*60*60)...
A symbol for the units, another symbol for ten, another for 60, superposition of the previous two for 600, another for 3 600, superposition of the symbol ten and 3 6000 for 36 000...

For instance u representig the unit, t the ten , s the sixty, r the 600, and o the 3 600, p the 36 000 : pppp ooooo rrrrr ss ttttt u would be 36000+36000+36000+36000+3600+3600+3600+3600+3600+600+600+600+600+60+60+10+10+10+10+10+1=164571
The symbols where grouped in paterns to facilitate reading.
(source Histoire universelle des chiffres by George Ifrah, editor Seghers 1981)

Xyzzy was quicker to answer :-)

davieddy 2007-03-08 12:08

[quote=Xyzzy;100223]We're assuming this is not a rhetorical question:

[URL]http://en.wikipedia.org/wiki/Babylonian_number_system[/URL][/quote]

It wasn't. Remembering ~26 letters of the alphabet seems
to be a sensible limit.
BTW was that the royal "we"?

David

cheesehead 2007-03-08 17:06

[quote=davieddy;100225]BTW was that the royal "we"?[/quote]No. Xyzzy uses the [I]editorial we[/I] (he being head honcho hereabouts), or perhaps a generic third person (See the "Atypical uses of we" section at [URL]http://en.wikipedia.org/wiki/We[/URL]), or [I]pluralis modestiae[/I] (rather than [I]pluralis majestatis[/I], the [I]royal we[/I]).

OTOH, Xyzzy does have a tendency to do things like inserting false quotations (e.g. [I]"I quote more ... all day!"[/I]) between one's nym and avatar in the left margin, which seem more imperial than editorial.

davieddy 2007-03-08 19:07

[quote=cheesehead;100238]OTOH, Xyzzy does have a tendency to do things like inserting false quotations (e.g. [I]"I quote more ... all day!"[/I]) between one's nym and avatar in the left margin, which seem more imperial than editorial.[/quote]

Speaking of which, what does mine mean?

Xyzzy 2007-03-08 22:49

[quote]Speaking of which, what does mine mean?[/quote]

:google:

Xyzzy 2007-03-08 23:00

BTW, for the record, the actions that we take (Xyzzy, and his evil twin Yzzyx) are, for the most part, random, malicious and devoid of meaning.

Some misguided souls have hypothesized that there is a relationship between various psychotropic medications and our behavior but we dismiss that line of thought as a desperate attempt to make something utterly pathetic and unfathomable into something sensible. Sometimes things really stink, no matter how much perfume you put on them.

:mally:

cheesehead 2007-03-09 03:45

[quote=cheesehead;100238]Xyzzy uses the [I]editorial we[/I] (he being head honcho hereabouts), or perhaps a generic third person (See the "Atypical uses of we" section at [URL]http://en.wikipedia.org/wiki/We[/URL]), or [I]pluralis modestiae[/I] (rather than [I]pluralis majestatis[/I], the [I]royal we[/I]).[/quote]
[quote=Xyzzy;100287]BTW, for the record, the actions that we take (Xyzzy, and his evil twin Yzzyx)[/quote]Well, now that "Yzzyx" is on record, I wish to amend my previous statement.

Xyzzy's earlier use of the [I]editorial we [/I]has now progressed into the [I]delusional we[/I]. That is, his [I]use[/I] has progressed; Xyzzy himself is not actually delusional, but seems desirous of presenting that facade.

mfgoode 2007-03-09 05:30

Irish.
 
[QUOTE=davieddy;100252]Speaking of which, what does mine mean?[/QUOTE]

Its Irish for "a thousand welcomes"

I thought you would get it in my previous post to you when thats how I signed off but you were too busy with my verbosity.

Mally

davieddy 2010-06-27 03:48

Cracked it!
 
[quote=mfgoode;97918]:smile:

Here is a simple problem from the Maths Tripos.

ABC is an isoceles triangle, whose vertex angle at A is 20* . The point D is on AC such that DBC is 60*. E is on AB such that ECB =50. Find BDE

Mally :coffee:[/quote]

Three years ago, this puzzle was entertaining philmoore and me.
I have revisited it and come up with this solution:

[spoiler]Let F be the reflection of B in AC and
let G be the reflection of C in AF.
AD=DB and AGB is equilateral
Let DG intersect AF at H
DGF is 50 degrees so AH=AE

BDE=FDG=30[/spoiler]

David

.

davieddy 2010-06-27 05:13

Hint to graphics fans
 
(Myself included)

A picture must be worth at least 50 words:smile:

David

PS Or the other way round
(as the actress said to the bishop)


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