OK, first of all, if you can spare 5 mins, it would be great if you could take part in this online experiment into facial appearance and honesty. Participate here. many thanks.
Onto the puzzle. Here are ten matchsticks making up an equation based on Roman numerals….
Can you move ONE matchstick and make the equation correct? You are not allowed to remove the matchstick completely and can’t leave any blanks (e.g., XI + = XI isn’t allowed). At least one of the solutions is very simple and one is very sneaky. How many solutions can you come up with?
As ever, please do NOT post your answers, but so say if you have solved it and how long it took. Answer on Monday!
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June 25, 2010 at 5:40 am |
One answer instantly; no doubt there are a number of others…
June 25, 2010 at 5:41 am |
I found 2 answers, it took me two minutes.
June 25, 2010 at 5:44 am |
It took under a minute for one solution, probably the easiest one.
June 25, 2010 at 5:48 am |
My friend and I looked at this and came up with the one blindingly obvious solution right away. It took us about ten more minutes to find 2 other solutions that fit, and 2 more that might fit, depending on how much of a stickler we want to be.
June 25, 2010 at 6:21 am |
Got the 1 solution in 30 sec s ,cant see the others yet though
June 25, 2010 at 6:31 am |
One answer, straight off — gotta go work, now, though!
June 25, 2010 at 6:34 am |
Roughly 3 seconds. Straight Forward. I have to continue my programming.
June 25, 2010 at 6:47 am |
hmmm… there is several ways to turn this in a correct expression but an equation?… not so easy… tic-tac-tic-tac… I have to go the john, let’s commit the image to the memory and try to find it there… …is that? not that… this? not this… tic-tac-tic-tac-…-toe
In the end, the solution is very simple, and not even the delays imposed by physical multitasking justifies the more or less 6 minutes I took to find it
(Richard’s returns to the task of finding the simplest or maybe the easiest puzzle of the world)
June 25, 2010 at 6:56 am |
At least two answers in a few seconds. And one answer where I don’t need to move any match stick
June 25, 2010 at 7:01 am |
Even I got this one in a second…
June 25, 2010 at 7:05 am |
Bloody hell, I hadn’t read the question and I had the answer. So very like the “split clock face” puzzle earlier in the year.
June 25, 2010 at 7:11 am |
I have 2 solutions in about 2 mins, 1 simple and straightforward the other requiring a knowledge of mathematical equations (so I assume its the sneaky one)
June 25, 2010 at 7:39 am
I straight away within a second or two, the second within a minute after seeing that James suggested one that required a knowledge of mathematical equations.
June 25, 2010 at 7:15 am |
It took 2 minutes or so to find 2 answers. Nice puzzle.
June 25, 2010 at 7:16 am |
Got two for it, with the same answer for both.
June 25, 2010 at 7:17 am |
Got two in 1 minute and another one (not sure if it is acceptable) in another minute or two.
June 26, 2010 at 12:53 pm
Same here
June 25, 2010 at 7:19 am |
I have 3 solutions – 1st 10 seconds, 2nd 1 minute, 3rd 90 seconds.
June 25, 2010 at 7:21 am |
2 answers? (Noky and Roland)… I found one solution in 2 minutes.
June 25, 2010 at 7:22 am |
3 answers within a minute, think I got the least obvious one first.
June 25, 2010 at 7:23 am |
Got 2 answers under 1 minute, both were very easy. No sneaky ones tho
June 25, 2010 at 7:25 am |
Easy answer in seconds, second answer in a couple of minutes.
June 25, 2010 at 7:27 am |
Two answers jumped out at me instantly and one of them is probably the sneaky one.
June 25, 2010 at 7:28 am |
Woohoo finally got one!
June 25, 2010 at 7:30 am |
3 answers in 10 minutes. 1 very simple and 2 tricky. Another 3 if you dont demand oerfection
June 25, 2010 at 7:38 am |
Two solutions in 1 minute. another 2 minutes later.
June 25, 2010 at 7:39 am |
Found two simple solutions, but the sneaky one is evading me. Oh, well.
June 25, 2010 at 7:52 am |
I saw the first really easy solution very quickly and have ideas on a couple of others but my mind is busy on other stuff so will come back to it when I’m less distracted.
June 25, 2010 at 7:52 am |
Three solutions. 30 seconds for the first two, another 3-4 minutes for the third.
I wonder if the others who found 3 solutions found the same ones…
June 25, 2010 at 7:53 am |
Two answers in 1 minute. Both not sneaky, though. Will keep staring for more anwers.
June 25, 2010 at 7:55 am |
I got one, but I’m sure it doesn’t count.
Oh! And another one, which probably does.
June 25, 2010 at 7:55 am |
I got one within seconds, presumably the easy one. After a couple minutes did not figure out the other.
June 25, 2010 at 8:04 am |
2 answers in a seconds, a third after a minute
June 25, 2010 at 8:11 am |
one answer under a minute. has to be the easy answer!
June 25, 2010 at 8:16 am |
I got one solution in half a minute, though it is not a very elegant one. Later at work, I saw (face palm!) the obvious solution.
June 25, 2010 at 8:21 am |
I saw one solution almost immediately (20 seconds?) and another in a further 45 seconds or so… may seem if any other come to mind with actual thought…
June 25, 2010 at 8:26 am |
Got two solutions very quickly but I’m not sure if one is legit or not. It turned out to be an answer of a similar one I have seen on this site.
June 25, 2010 at 8:31 am |
Took a couple of minutes to get two slightly cheeky possibilities before the very obvious one leapt out at me. But depending on how strictly you interpret the word ‘equation’, you might not be able to get away with some of the sneaky ones.
June 25, 2010 at 8:32 am |
few sec
June 25, 2010 at 8:38 am |
4 solutions 1 Minute
June 25, 2010 at 8:48 am
Just Found 4 more so im at 8 in 2 minutes
June 25, 2010 at 10:37 am
Took me Another 3h to find out that One is wrong
remaining 7
June 25, 2010 at 8:41 am |
well and good
seconds
June 25, 2010 at 8:47 am |
I found 4 possible answers in a couple of minutes. At least 2 of them might be considered a bit of a cheat though
June 25, 2010 at 8:51 am |
5-6 answers, depending on how sneaky you’re allowed to be.
June 25, 2010 at 9:06 am |
Two solutions in about a minute. Gonna look for more when I get home tonight.
June 25, 2010 at 9:27 am |
Three solutions in one minute
June 25, 2010 at 9:45 am |
I’ve found 2 very simple answers in a few seconds.
June 25, 2010 at 9:45 am |
Got two answers almost instantly.
June 25, 2010 at 9:48 am |
Two solutions, namely the simple and the sneaky one, in about one minute
June 25, 2010 at 9:54 am |
got 2 answers in seconds
June 25, 2010 at 10:00 am |
About five seconds for an easy one, another five for a ‘sneaky’ one. I’m usually quite poor at these.
June 25, 2010 at 10:01 am |
I found 3 simple solutions in about 30 seconds, but haven’t found the sneaky one yet.
June 25, 2010 at 10:01 am |
The easy one came in seconds. I also have one I consider particularly sneaky
)
June 25, 2010 at 10:03 am |
Duh! took about 2 mins with an interuption to get what I presume is the easy one. Now berating myself for being stoopid as once you see it it is so obvious.
Haven’t seen the harder solution yet but then equations ain’t my strong point.
June 25, 2010 at 10:16 am |
I looked at it, thought about it, went to the survey for a minute (couldn’t get the images to upload from the survey) so I went back to the puzzle. Upon a second look I got it in about 30 secs. or so. I must have gotten the easy answer and not the tricky one.
June 25, 2010 at 10:32 am |
I found 2 solutions to Richard’s puzzle (moving one match) and a third solution that involves moving no matches at all.
June 25, 2010 at 10:36 am |
Got two solutions almost immediately. Not finding any others yet. Or maybe I’m being too strict.
June 25, 2010 at 10:39 am |
I got the simple answer straight away … I think I might come back to it later when I have more time to see how many other answers I can get … I like this puzzle!
June 25, 2010 at 10:39 am |
‘sneaky one’ instantly.
‘obvious one’ about 3 minutes.
Can’t believe it took me so long!
June 25, 2010 at 10:59 am |
Took me a second or two for the obvious one, about ten seconds for the sneaky one. Assuming I in fact found the sneaky one, and there weren’t actually two obvious ones.
June 25, 2010 at 11:24 am |
3 answers in 30 seconds, along with a further answer that doesn’t require moving any matchsticks.
Too easy.
June 25, 2010 at 11:25 am |
The trouble with the (otherwise excellent) Friday Puzzle is it encourages some pretty insufferable people to post about how clever they are without allowing them to prove it.
Why not close the comments until the solution is revealed? That way we’d be spared people leaving statements like “Roughly 3 seconds. Straight Forward. I have to continue my programming” which is little more than self-aggrandisement (not to single out Lt Cdr (ret) Nazri in particular, there are plenty of others).
June 25, 2010 at 11:27 am |
one sneaky one instantly, one cheaty one at 30 seconds and then what i think is the real answer at 60 seconds.
June 25, 2010 at 11:46 am |
I took the Honest or dishonest test and started laughing all the way through it.
some people look a bit….. different….
June 25, 2010 at 12:03 pm |
4 solutions in a few minutes
June 25, 2010 at 12:30 pm |
Got two simple ones in under a minute, still looking for a sneaky one.
June 25, 2010 at 12:33 pm |
A few seconds to get two possible solutions.
June 25, 2010 at 12:35 pm |
Two simple ones and two sneaky ones – in about ten minutes. A sneaky one first…
June 25, 2010 at 12:46 pm |
Unless I’m still just groggy from it being early and forgetting how Roman numerals work, there are two pretty easy solutions and they kind of mirror each other. One took a few seconds and the second about a minute.
I’m guessing there are at least a couple of trickier solutions that I haven’t picked up yet.
June 25, 2010 at 12:57 pm |
The simple one is too easy. I saw it as I read the equation and had to go back and see what the equation really said. Now I’ll have to try to find the sneaky one.
June 25, 2010 at 12:59 pm |
3 answers (2 in a few seconds, 1 sneaky within a minute)
June 25, 2010 at 1:02 pm |
Got a solution in less than a second. It’s wrong, but i have a plane to catch.
June 25, 2010 at 1:09 pm |
Two easy ones – both by moving the same match to different locations. I’ll have a further study this weekend to see if I can get any of the others.
I assume we’re not allowed to use the triple bar symbol or place two matches so they touch each other along their entire length, thus giving the illusion of a single match…
June 25, 2010 at 1:17 pm |
I found four solutions in about five minutes, one of them instantly.
June 25, 2010 at 1:22 pm |
20 sec
June 25, 2010 at 1:23 pm |
I haven’t looked at the puzzle yet, but I clicked over to take the facial appearance/honestly experiment and got a message that the study is closed~
June 25, 2010 at 1:33 pm |
5, between my officemates and I in about 3 minuets: 2 simple, 2 cheekier, 1 cheekiest.
June 25, 2010 at 1:48 pm |
Two answers almost instantly; the third one (slightly more questionable) about 30 seconds later…
June 25, 2010 at 2:09 pm |
2 solutions are obvious keeping the equal sign.
Others are possible by changing equal in something other…
June 25, 2010 at 2:10 pm |
I got two answers. But I really wonder if the second I found is the sneaky one…
June 25, 2010 at 2:11 pm |
almost instantly. easy peasy
June 25, 2010 at 2:15 pm |
[...] 2010/06/25 in Uncategorized OK, first of all, if you can spare 5 mins, it would be great if you could take part in this online experiment into facial appearance and honesty. Participate here. many thanks. Onto the puzzle. Here are ten matchsticks making up an equation based on Roman numerals…. Can you move ONE matchstick and make the equation correct? You are not allowed to remove the matchstick completely and can't leave any blanks (e.g., XI + = XI isn't allowed). … Read More [...]
June 25, 2010 at 2:17 pm |
Don’t want to sound like the others, but 2 in 2 minutes. Still a fantastic teaser to start the weekend! Thank you!!
http://danjswade.wordpress.com
June 25, 2010 at 2:18 pm |
That’s an easy one.
June 25, 2010 at 2:20 pm |
i can only find 2…used about 3-4 minutes
June 25, 2010 at 2:26 pm |
I find one solution and it took me 30 sec. IX + I = X
June 25, 2010 at 2:43 pm
Psst! Read the text that accompanies the puzzle. ESPECIALLY the last sentence.
June 25, 2010 at 2:27 pm |
This isn’t the real Friday Puzzle, right? Come on. Be serious. Give us the real puzzle, Professor Wiseman!
June 25, 2010 at 2:29 pm |
Ok, took me plus 1 min to find another solution XI – I = X
June 25, 2010 at 2:31 pm |
another solution again add 30 sec X + I =/ (different from) X
June 25, 2010 at 2:33 pm |
[...] OK, first of all, if you can spare 5 mins, it would be great if you could take part in this online experiment into facial appearance and honesty. Participate here. many thanks. Onto the puzzle. Here are ten matchsticks making up an equation based on Roman numerals…. Can you move ONE matchstick and make the equation correct? You are not allowed to remove the matchstick completely and can't leave any blanks (e.g., XI + = XI isn't allowed). … Read More [...]
June 25, 2010 at 2:35 pm |
Three solutions two obvious, one sneaky, five minutes.
June 25, 2010 at 2:40 pm |
One answer, instantly
June 25, 2010 at 2:47 pm |
2 solutions within 30 seconds. A few more within a minute or two more. Even managed to solve it without moving any matches, not that that is in the rules.
Felt to me like we just did this puzzle recently before I even put on my thinking cap. Or was I thinking of a similar puzzle?
June 25, 2010 at 2:50 pm |
I solution in 15 seconds
June 25, 2010 at 2:51 pm |
Three seconds, I have an answer, I have no idea if it is correct. An equation just jumped out at me.
June 25, 2010 at 2:54 pm |
Took me around 5 minutes to find 3 answers to the equation ^^
June 25, 2010 at 3:00 pm |
I’ve got what I imagine is the simple one! Took about one and a half/two minutes.
June 25, 2010 at 3:03 pm |
Took about a minute. Was looking for a much more clever solution than the one I found. In the end, it’s just about exploiting what’s there in front of you.
June 25, 2010 at 3:07 pm |
One simplest solution came to my mind, but then …. I know that I can do it without moving any matchstick
June 25, 2010 at 3:08 pm |
visit upuptown.wordpress.com
June 25, 2010 at 3:08 pm |
Simplest one came in a second. Another sneaky(?) one took just a few moments more.
June 25, 2010 at 3:09 pm |
Oh, got it. Took a couple of minutes. Slightly embarrassing considering how simple it was
June 25, 2010 at 3:15 pm |
Four solutions in two minutes.
June 25, 2010 at 3:18 pm |
After a minute or to of complex “what ifs”- I could move the diagonal line and make a caret and… the simple solution popped into my mind, and I felt kinda stupid.
June 25, 2010 at 4:01 pm |
2 solutions in 45 seconds approx
June 25, 2010 at 4:07 pm |
Five solutions so far, first one under a minute. Not the blindingly obvious one either – was trying to be far too devious for my own good.
June 25, 2010 at 4:17 pm |
Got one without moving any matchstick
June 25, 2010 at 4:29 pm |
Got one on my 3d mental attempt or so.. so like less than 20 seconds
June 25, 2010 at 4:37 pm |
Got 3 in total, two fairly quickly and a minute for the third
June 25, 2010 at 4:52 pm |
Just stopped at first solution that came to mind.
June 25, 2010 at 4:54 pm |
I knew what the simple (and obvious) one was before I even read the description of the puzzle, seeing the blatantly incorrect equation as a giant image.
I guess I’ll try to figure out some sneaky ones.
June 25, 2010 at 5:59 pm |
I think I’ve found seven possible answers in a few minutes…
June 25, 2010 at 6:09 pm |
puzzle that dont puzzle you!
June 25, 2010 at 6:11 pm |
One simple answer in about half a minute. Another simple answer about a minute later. No sneaky answers yet — I assume that’s where the real fun of this puzzle is. I do like the fact that there is a solution that involves moving *no* matches.
June 25, 2010 at 6:13 pm |
Got one answer in about 10 sec.
June 25, 2010 at 6:14 pm
Second answer about 10 sec later!!
June 25, 2010 at 6:13 pm |
Richard, I see that the survey is now closed. If that’s intentional, maybe you could update this post to reflect that so readers don’t waste a click trying to go to it.
June 26, 2010 at 7:31 am
Yes, please let us know if you’ve already closed the survey this early. I would have loved to participate. If it’s an error, please let us know that too.
June 25, 2010 at 6:33 pm |
3 solutions, and a fourth one where you don’t move anything!
June 25, 2010 at 7:46 pm |
I saw three solutions right away and maybe more if you are allowed to mess with the equal sign.
June 25, 2010 at 8:00 pm |
Well, actualy, it is possibly to make this thing correct without moving any matches, and dont add or subtract matches. So, lets see if anyone can do it WITHOUT doing anything with the matches at all…
June 25, 2010 at 8:08 pm |
A simple solution within 30 secs, two more about five mins later after I watched the football for a bit. Good idea, that – occupy your mind with something else and then approach the puzzle again. I wonder where I heard that?
Hopefully italics are acceptable…
June 25, 2010 at 8:17 pm |
Yes not hard if you work out what two numbers will make the total
June 26, 2010 at 12:11 am |
[...] It’s the Friday Puzzle! OK, first of all, if you can spare 5 mins, it would be great if you could take part in this online experiment into [...] [...]
June 26, 2010 at 1:04 am |
Instantaneous. But can’t we make it pretzel sticks next time? They go better with a Friday beer.
June 26, 2010 at 1:54 am |
3 Solutions, one is obvious, and took me the longest to find (duh!), the sneakiest solution, well it is a bit fat, but does not equal the less sneaky one.
June 26, 2010 at 3:20 am |
I got the obvious one in about 20 seconds and I see one more but it took about 10 minutes to see it.
June 26, 2010 at 3:22 am |
Finally!!! 2 solutions in one minute. Yeah!
June 26, 2010 at 4:43 am |
I found two really easy ones in seconds! I’m usually horrible at his riddles so I’m happy this time
June 26, 2010 at 5:47 am |
I got 2 answers instantly but I don’t know if the second is a ‘legal’ move. Curious to see if it is.
June 26, 2010 at 6:53 am |
I came up with two solutions, both involving being sneaky in a symbolic manner…
June 26, 2010 at 6:54 am |
P.S., it took me 10 or so seconds.
June 26, 2010 at 8:18 am |
I THINK I could… however, can it be this simple? about 30 seconds.
June 26, 2010 at 8:44 am |
got the easy one:) BTW Survey us closed when I click???
June 26, 2010 at 3:11 pm |
I found one really easy, and other taking one out…
June 26, 2010 at 3:37 pm |
Found the two obvious ones, one sneaky and one ugly/sneaky.
And the one that doesn’t require moving ANY matches.
June 26, 2010 at 5:18 pm |
Two solutions leaped out immediately! What fun!
June 26, 2010 at 8:45 pm |
June 27, 2010 at 12:33 am |
First answer in about twenty seconds, second answer in two minutes, there are probably more. I like the math puzzles, but maybe a bit trickier…
June 27, 2010 at 2:58 am |
One solution almost immediately, a second one in under a minute.
June 27, 2010 at 2:58 am |
One second for the first. Longer to post a reply ‘cos I clicked the wrong link. Also, was so excited, I didn’t read the next part of the question about other answers. ADHD can be a nuisance sometimes.
June 27, 2010 at 3:01 am |
ps. got 4 answers in about 10 sec, but only after being prompted by previous posts.
June 27, 2010 at 3:52 am |
I saw one immediately, and then another in under a minute.
June 27, 2010 at 9:37 am |
only 3
June 27, 2010 at 1:34 pm |
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June 27, 2010 at 8:47 pm |
3 answers, one right away, one after about 10 secs, and another one some time later when looking at it again. Not sure that any of them are particularily sneaky, although the last one might not be too straightforward.
June 28, 2010 at 1:23 am |
1 sec for the the easy one. the more sneaky one i have no idea..
June 28, 2010 at 2:00 am |
It look me less than a minute to find two answers
June 28, 2010 at 6:52 am |
[...] dejar un comentario » OK, first of all, if you can spare 5 mins, it would be great if you could take part in this online experiment into facial appearance and honesty. Participate here. many thanks. Onto the puzzle. Here are ten matchsticks making up an equation based on Roman numerals…. Can you move ONE matchstick and make the equation correct? You are not allowed to remove the matchstick completely and can't leave any blanks (e.g., XI + = XI isn't allowed). … Read More [...]
June 28, 2010 at 7:33 pm |
about 10 seconds. should have read the rules more carefully
June 29, 2010 at 8:11 am |
Took me about a minute to find two answers. Clever
Thanks
http://afscience.wordpress.com
June 30, 2010 at 3:26 am |
2 answers in under a minute.
July 7, 2010 at 8:55 pm |
Took me a glance at it to solve.
October 31, 2010 at 3:04 pm |
EZ!!! i anser in 20 secs!
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