mental_floss magazine
SUBSCRIBE >
GIFT SUBSCRIPTIONS >
DIGITAL SUBSCRIPTIONS >
subscriber services >

I loved sorting through the solutions (and reading the related explanations) for Friday’s riddle, so here’s a new one for this weekend’s Weekend Genius Challenge:
Be it days or nights
It measures our slumber
But with letters in order
It is THE only numberWHAT is it? And WHY?
As with many riddles, they may be multiple near-correct answers, but of course, we’re only looking for one. Send us your guess by commenting to this post, and please remember that submissions are moderated, so your post will NOT show up right away. If you’re the first to correctly match our answer, you’ll win a T-shirt of your choice from the mental_floss store. And my undying admiration.
Good luck!
FORTY
Idioms, size L
posted by Jack da Bomb on 4-12-2008 at 12:02 pm
EON a measure of time
ONE the first and singular number
posted by Patrick B on 4-12-2008 at 12:05 pm
8
8 hours of sleep
EIGHT (letters are in alphabetical order)
No clue why/if it works for the first and last lines though.
posted by Josh W on 4-12-2008 at 12:19 pm
Sorry.
My explanation:
FORTY is the only number with letters in alphabetical order, it measures days and nights (FORTY days and FORTY nights), and it measures sleep (FORTY winks).
posted by Jack da Bomb on 4-12-2008 at 1:39 pm
Seven
posted by Jack on 4-12-2008 at 1:40 pm
Ah, must be FORTY
posted by Jack on 4-12-2008 at 1:41 pm
Jack’s right,
it’s FORTY
posted by Hareesh on 4-12-2008 at 2:07 pm
Yes, forty, it is now so obvious. Well done.
posted by Tim on 4-12-2008 at 7:38 pm
FORTY
As in Forty winks!
posted by Chris H on 4-13-2008 at 1:14 pm
The answer is 8, The reasons are:
1. Be it days or nights
8 Days & 8 Nights, From the Jewish holiday of Chanukah
2. It measures our slumber
8 Hours of Rest
3. But with letters in order
The number 8 as seen on your phone has the letters, “T,U,V” in order
4. It is THE only number
Turn 8 sideways and you will see just how infinite the number really is.
posted by chris on 4-13-2008 at 6:11 pm
Forty.
Forty winks.
Letters are in alphabetical order. Forty is the only number in English that does this.
Rocket surgeon. Medium.
Thanks.
posted by Jason on 4-13-2008 at 10:08 pm
Sun.
Day or night
It measures our slumber.
But with letters in order
It is the only number.
UNS=Unified Numbering System
posted by Milton X. on 4-13-2008 at 11:11 pm
Z’s
posted by Kevin McDonald on 4-14-2008 at 8:02 am
The answer is Harry Truman.
Harry Truman worked all day and night.
Harry Truman would count the hours everyone slept in America as part of some twisted big brother plot.
Harry Truman was notorious for being a stickler about keeping his mail(letters) in order by geographical origin(west to east)
Harry Truman in numerology adds up to just ONE number.
posted by Gatsbay on 4-14-2008 at 8:06 am
LMAO.. Gatsbay should win a shirt for an inventive answer.
I immediately LOL’d at Harry Truman before I even read his explanation.
posted by Kelly on 4-14-2008 at 12:28 pm
REM (rapid eye movement)
EMR (Electronic Medical Number)
posted by Ted Duke on 4-14-2008 at 2:05 pm
I agree with Kelly, I am still laughing out loud!
posted by Alisia on 4-14-2008 at 4:00 pm