This triangle is constructed from 10 coins. What is the smallest number of coins that need to be moved to make the triangle point downwards?
As ever, please do NOT post your answers, but do say whether you think you have solved it and how long it took. Solution on Monday.
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Richard Wiseman 
Feel very easy, done in about 20 seconds
Took me about 2 seconds. Assuming I’m right…
Same.
I didn’t even finish the question 😦 very old puzzle that I have seen many times before.
Done it. 1 minute.
Done in about 5 seconds.
If I’m right — about 30 seconds.
Are they 5p or 10p pieces?
ROFL
Done – in about 20 seconds.
Done. But I think my answer is cheating kind of. about 10 seconds.
Yep, 20-30 seconds.
Seen it before, took 3 seconds back then too.
Got one solution in 5s but another improved one in another 2-3 minutes.
easy! 10 seconds
Not too long today but only if I got the correct answer
10 seconds. Maybe too easy? I guess I’ll find out monday…
Instantly…
Hope i’m right.
got it,took a couple of seconds (hope i’m right)..
Yes, fairly easy (for a change).
Depending on how you read the question, 2 solutions in a few seconds 🙂
Read it again. The problem asks for the smallest number. That means that there is only one solution.
There is only one solution, however what that is depends on how you interpret Richards question…
About 30 seconds. If I’m right. 🙂
Done in a couple of seconds (I think!)
about 5 sec assuming i am right. i think even two possibilities based on how its worded
Did this quickly but then I have seen it before.
Well, I think I-ve done it, but there may be a better answer, I just haven-t found it.
Anyway, depending on how you look at it, the triangle could already be pointing downwards left or downwards right.
None, you just have to view it in an Australian frame of reference…
Harder next time please 😉
Got it instantly.
but it already points downwarts.. in a rightish downwards direction and in leftish downward direction. …
If you want it to point straigth down, … also possible, 3 seconds..
without moving the upper and lower boundaries of the triangle an additional coin is required to be moved..
I got one answer in about 5 seconds, then a correct answer about a minute or two later.
sorry, have anohter (presumably incorrect solution).. after a few minutes.. definitivly including the minimum of coins to be moved…
About a minute. Couldn’t find 10 similar coins though!
See, I think I’ve done it and it was far too easy so no doubt on Monday the answer will be something like ‘π x happiness’
Oh how Mondays make me feel stupid.
That was too easy. 2 seconds.
If someone get’s less that that though, I’ll be *really* impressed
Done! Three seconds! (Although I had the feeling I had seen something similar somewhere…)
Got it wrong in about twenty seconds.
Got it right in a further twenty and made a 25% saving….
About 5 seconds, assuming I am right… I can’t find an alternative with fewer moves.
It must be right.
!
Solved this in 0.1237 seconds
I’ve seen it before, so about 1/2 s after seeing the illustration.
I solved it yesterday
About 30 secs to get one answer and then about another 45 secs to get a better one.
Two solutions in 10 seconds. Because the puzzle is old, or because I am.
Too easy, how about fewest moves to a dodecahedron? or a rabbit? or hyperlipoproteinurea?
it can be done in no moves- just walk around to the other side of the table
That’s exactly what I was going to say. 🙂
there is the obvious way and then the trick which we normally miss – i advise people to recount their moves before monday
Your link to the free puzzles is giving a Error 404 – Not Found page.. . .Hey, wait a minute. Is that the puzzle? I’m confused.
I too got a quick answer in a few seconds and then improved it with a minutes thought.
Done it. Half-a minute? I’m quite sure. 🙂
Good old Professor Layton taught me this one.
simple….but perhaps I’m just very bright!
I see 2 possible answers. There is also an interpretive shade of grey in the possible answer.
Really? That took a couple of seconds to work out.
It took me about a minute to see the core pattern. I will check in on Monday to see if I got the correct answer.
0s
Very quickly, think I’ve seen it before tbh. (Nothing wrong with that though)
Isn’t it already pointing downwards? If you assume that one of the bottom corners of the triangle is the point. 5 seconds.
Depends on the exact rules. I found three different solutions, took me about 1 minute for all of them.
5 secs
If you are able to see the shape not as a triangle, but a composite of two items (one which will remain unchanged) the answer jumps out at you.
Zero: I turned my laptop around…
Again I don’t think this has anything to do with maths, but I’m going to pretend and have a shot.
Ah. I got one answer in about 20 secs, but then spent another minute seeing if I could find a better one. I believe I have the right answer now. Can’t see a better solution
About 2/3 seconds. And looking into the future, I can see it’s right, so fairly confident…
Two answers – one involving three coins fewer than the other.
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