OT A simple math puzzle


The solution to this puzzle is probably very simple.

I will probably be embarrassed by how simple the solution actually is.



On first glance, 15 seems about right (i.e. 36 minus 21 = 15 and 28 minus 15 = 13).

Edited: 6 May 2007, 12:27 p.m.


How does the 21 - 13 give 7, then?

Edited: 6 May 2007, 12:34 p.m.


Good catch. Obviously, I didn't take the time to finish the sequence :-)

Good thing my answer was of the non-committal type, with generous use of "escape" language, such as, "On first glance.." and "seems about right..".

Now I'm sounding like a politician :-)



One solution is 12. I wonder if there are more solutions. :-)

-- Richard



Can you describe how you arrived at your solution?




Perhaps Richard just didn't want to spoil the fun:

(9+9) + (7+2) = 27

(2+7) + (4+5) = 18

(1+8) + (3+9) = 21

and so on...



Edited: 6 May 2007, 6:34 p.m.



I used the same method to get the solution as Gerson. I summed the individual digits to get the next result.

Puzzles like this one always make me wonder if there is more than one way to solve them since the rules are very open-ended.

Thanks for the challenge.

-- Richard


I used the same method to get the solution as Gerson.

As a matter of fact, I didn't find the solution. You did. I just got curious and tried to discover how you had found it. If I didn't know the solution beforehand I would have probably voted for 15 and assumed the 21 at right was a typo :-)

The following might be easy and has only one solution, to my knowledge:

     ____  ___
|\/| \ / \ / |\/| ?
| | _\/_ /_\ |¯¯|



Yes, this one is very, very old:

| |
Best regards from V.


Please, explain...

-- Antonio


Hi, Antonio:

    Antonio posted:

    "Please, explain..."

      It's actually extremely simple: the first four forms are
      just the ASCII representation of the shape of the digits 1,2,3,
      and 4 with their mirror images prepended.

      The next element thus is to be an ASCII representation of the
      shape of a 5, with its mirror image prepended.

Best regards from V.



I'm so dumb...

-- Antonio


Actually this is not so easy, as we tend to see the symbols as letters:

Roman numerals? :-)







Hi, PeterP:

    Actually, I've got nothing (yet). I've checked the usual
    accounts but nothing there from you, unless you were telling
    me that a recently deceased relative has left me 6 million
    sterling pounds in his will and that I should send my bank
    account details for the transfer of the funds to be made.
    If that was the case, sorry but I decline the kind offer,
    I'm far too modest a person, as everyone knows, and wouldn't
    know what to do with that much money, it would spoil my
    healthy habits for sure.

    Now seriously, did you remember to include the string "HP CALCS" in the
    subject line, as instructed in my web page ? Else, *anything*
    sent to my usual account (via this MoHP form, for example)
    without including such a text string in the subject is automatically and
    invisibly redirected to the trash bin, sight unseen.

    Thanks for whatever it was and

Best regards from V.


my mistake, really sorry. Forgot about the subject line. Mistake corrected. Thanks for the reminder!




Oh, I see now!

I got off on the wrong foot since 99/72 = remainder of 27 and 54/27 = remainder of 18. I lost it after that.

At least the solution was a little bit tricky. I don't need to be that embarrassed.


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