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How many triangles?

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  • 11-07-2009 4:51pm
    #1
    gillo_100
    Closed Accounts Posts: 135 ✭✭


    Here is a neat puzzle I came across.
    How many triangles in the attached picture?

    There is no funny tricks to this just count the triangles, also apologies for my bad drawing, bottom left corner should be joined, also where the lines meet at the centre should all be one point there are no very small triangles here.

    I know the answer and will post it in a number of days, with solution if wanted.


Comments

  • Options
    #2
    Chuckels
    Registered Users Posts: 15 ✭Chuckels


    I probably confused myself as to which ones I had and had not counted, but there's at 47 at least. Possibly more, but I got 47.


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    #3
    gillo_100
    Closed Accounts Posts: 135 ✭✭gillo_100


    Ah, I'd nearly forgotten about this, not sure why no one else replied.

    Your close with 47, but its not quite right. I'll leave it till the end of the day to post answer, see if anyone else wants to have a try. Also the drawings of solution I did out are on home PC.


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    #4
    jimmid098
    Closed Accounts Posts: 56 ✭✭jimmid098


    i think im blind i only count 26


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    #5
    CR 7
    Registered Users Posts: 3,691 ✭✭✭CR 7


    I got 33, but i'm using my phone so not the easiest to see, unless its zoomed in so far it cuts out some of it.


  • Options
    #6
    anti chris-t
    Closed Accounts Posts: 107 ✭✭anti chris-t


    i got 45 but not too sure


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  • Options
    #7
    gillo_100
    Closed Accounts Posts: 135 ✭✭gillo_100


    55

    I was amazed when i heard there was that many.

    5 symmetrical around the vertical axis.
    For the rest you only need to look at one side of the triangle and then double as one side is a mirror of the other. I'll try get up pics if people like, or you can try find them all yourself.


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    #8
    Ro: maaan!
    Registered Users Posts: 6,592 ✭✭✭Ro: maaan!


    gillo_100 wrote: »
    55

    I was amazed when i heard there was that many.

    5 symmetrical around the vertical axis.
    For the rest you only need to look at one side of the triangle and then double as one side is a mirror of the other. I'll try get up pics if people like, or you can try find them all yourself.

    Cba counting them all out. But there are at least 9 that cross the center vertical line, not 5. Not really sure if that's what you meant. Or if when you say "look at one side" you actually mean one side of the overall triangle or if you mean just don't count the symmetrical equivilant of anything regardless of whether it crosses the center vertical line or not.


    ...Maybe I should just count them all out. :D


  • Options
    #9
    Pal
    Closed Accounts Posts: 4,115 ✭✭✭Pal


    52 found


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    #10
    gillo_100
    Closed Accounts Posts: 135 ✭✭gillo_100


    Ok here is the solution.

    First pic has 25 that can be mirrored around the central axis to make 50. Some of these cross over the central axis but aren't symetrical so can be counted twice.

    Second pic has the 5 that are symetrical around the central axis, so have no mirror image.

    Pics are kinda small but if you zoom in should be able to make them all out.


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