# metric conversion **URL:** \ **Category:** Factual Questions\ **Created:** [March 16, 2003, 11:43pm UTC](https://boards.straightdope.com/t/metric-conversion/161872 "2003-03-16T23:43:06Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![JillGat](https://avatars.discourse-cdn.com/v4/letter/j/9fc29f/32.png) [@JillGat](https://boards.straightdope.com/u/JillGat)\ **Post date:** [March 16, 2003, 11:43pm UTC](https://boards.straightdope.com/t/metric-conversion/161872/1 "2003-03-16T23:43:06Z")
We moved from the US (that still doesn’t use metric) to a Caribbean country and now my 11 year old daughter has homework I don’t understand. She has to figure this out: 4 kg 3 hg 5 dag x 4 Most of these she does well, but we don’t know what “dag” is. Anybody else? ---
**Author:** ![GTPhD1996](https://avatars.discourse-cdn.com/v4/letter/g/97f17d/32.png) [@GTPhD1996](https://boards.straightdope.com/u/GTPhD1996)\ **Post date:** [March 16, 2003, 11:52pm UTC](https://boards.straightdope.com/t/metric-conversion/161872/2 "2003-03-16T23:52:12Z")
> [@](#): > > \*Originally posted by JillGat \* > \*\*We moved from the US (that still doesn’t use metric) to a Caribbean country and now my 11 year old daughter has homework I don’t understand. She has to figure this out: > > 4 kg 3 hg 5 dag x 4 > > Most of these she does well, but we don’t know what “dag” is. Anybody else? \*\* dag = dekagram = 10 grams GTPhD1996 ---
**Author:** ![Berkut](https://avatars.discourse-cdn.com/v4/letter/b/a88e57/32.png) [@Berkut](https://boards.straightdope.com/u/Berkut)\ **Post date:** [March 16, 2003, 11:57pm UTC](https://boards.straightdope.com/t/metric-conversion/161872/3 "2003-03-16T23:57:47Z")
Looks like 10 grams, or a dekagram. [http://ts.nist.gov/ts/htdocs/230/235/appxc/appxc.htm](http://ts.nist.gov/ts/htdocs/230/235/appxc/appxc.htm) ---
**Author:** ![Berkut](https://avatars.discourse-cdn.com/v4/letter/b/a88e57/32.png) [@Berkut](https://boards.straightdope.com/u/Berkut)\ **Post date:** [March 16, 2003, 11:58pm UTC](https://boards.straightdope.com/t/metric-conversion/161872/4 "2003-03-16T23:58:48Z")
Doh! ---
**Author:** ![JillGat](https://avatars.discourse-cdn.com/v4/letter/j/9fc29f/32.png) [@JillGat](https://boards.straightdope.com/u/JillGat)\ **Post date:** [March 17, 2003, 12:02am UTC](https://boards.straightdope.com/t/metric-conversion/161872/5 "2003-03-17T00:02:40Z")
4 kg 3 hg 5 dag x 4 4 kg = 4000 g 3 hg = 300 g 5 dag= 50 g x 4 = 17,400 g. 17400 gr divided by 1000 = 17.4 kg or 17 kg, 4 hg. Right? (Thank god I didn’t grow up in a country with a “Common Entrance Exam”) ---
**Author:** ![Achernar](https://avatars.discourse-cdn.com/v4/letter/a/e274bd/32.png) [@Achernar](https://boards.straightdope.com/u/Achernar)\ **Post date:** [March 17, 2003, 12:07am UTC](https://boards.straightdope.com/t/metric-conversion/161872/6 "2003-03-17T00:07:44Z")
Are you sure you’re not leaving out some addition signs or paretheses there? I know what the _da_ and _d_ prefices mean, and I use them when I want to be ostentatious, but do people in metric countries ever actually use them as a matter of course? ---
**Author:** ![Achernar](https://avatars.discourse-cdn.com/v4/letter/a/e274bd/32.png) [@Achernar](https://boards.straightdope.com/u/Achernar)\ **Post date:** [March 17, 2003, 12:09am UTC](https://boards.straightdope.com/t/metric-conversion/161872/7 "2003-03-17T00:09:02Z")
> [@](#): > > \*Originally posted by Achernar \* > Are you sure you’re not leaving out some addition signs or paretheses there? Er, on second thought, I see what the deal is. Nevermind. I’ve been thinking like a scientist for too long. Yes, 17.4 kg is right. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [March 17, 2003, 12:17am UTC](https://boards.straightdope.com/t/metric-conversion/161872/8 "2003-03-17T00:17:22Z")
Nah. We just say ‘This package contains 3.5 kilograms’ or ‘Next exit 500 metres’ or whatever, generally keeping to the ‘power-of-3’ multples. The only common exception around here is the centimetre. I remember how surprised I was to run across some European stuff mentioning hectolitres and centilitres… we just don’t use them in common discourse. I’ve _never_ heard anyone say ‘3 kilograms, 5 hectograms, 4 dekagrams, 2 grams’ as a way of naming one measurement. It looks like a way to artificially exercise the knowledge of the intermediate multiples… ---
**Author:** ![brianmelendez](https://avatars.discourse-cdn.com/v4/letter/b/65b543/32.png) [@brianmelendez](https://boards.straightdope.com/u/brianmelendez)\ **Post date:** [March 17, 2003, 12:20am UTC](https://boards.straightdope.com/t/metric-conversion/161872/9 "2003-03-17T00:20:20Z")
I would have taken a shorter approach: 4 kg 3 hg 5 dag x 4 = 4.35 kg x 4 = 17.4 kg ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [March 17, 2003, 1:59am UTC](https://boards.straightdope.com/t/metric-conversion/161872/10 "2003-03-17T01:59:21Z")
> [@](#): > > \*Originally posted by Achernar \* > \*\*I know what the _da_ and _d_ prefices mean, and I use them when I want to be ostentatious, but do people in metric countries ever actually use them as a matter of course? \*\* I grew up in a Metric country (Japan) and was introduced to the dl (deci-litre) in elementary school. I think it was a misguided effort by textbook publishers to allow use of nice numbers (integers or fractions of order 1) in classroom demonstrations.@ I haven’t seen it since then, and I’ve never seen any other use of **da** or **d** prefices. Almost all measurements are done by power of 1000 steps, as in science. The obvious exception is **cm** , of course. Also the **hecto** prefix is used for **hectare** (100 ares, 1 are=100 square meters), and the Japanese weather bureau uses hPa (hecto-Pascal) for atmospheric pressure. (They used to use millibar and wanted to keep the numbers the same.) ---
**Author:** ![Achernar](https://avatars.discourse-cdn.com/v4/letter/a/e274bd/32.png) [@Achernar](https://boards.straightdope.com/u/Achernar)\ **Post date:** [March 17, 2003, 5:33am UTC](https://boards.straightdope.com/t/metric-conversion/161872/11 "2003-03-17T05:33:12Z")
I do remember now, when I was in Italy, seeing cans of soda labelled “33 cl” for 33 centiliters. That wasn’t too hard to figure out, either.