It’s the Friday Puzzle!


As ever, please do NOT post your answers, but do say if you think you have solved the puzzle and how long it took. Solution on Monday.

Can you move one numeral and make the following equation correct?


I have produced an ebook containing 101 of the previous Friday Puzzles! It is called PUZZLED and is available for the Kindle (UKhere and USA here) and on the iBookstore (UK here in the USA here). You can try 101 of the puzzles for free here.


47 comments on “It’s the Friday Puzzle!

  1. Nusin misirli says:

    Correct ans 1 second

  2. Béranger says:

    A dash is NOT a numeral.

  3. Dennis says:

    Clever. It took a minute, but I might have missed if I hadn’t decided to brush up on math recently.

  4. -M- says:

    Got me thinking for a couple of minutes. Then the answer suddenly popped up.

  5. Niva says:

    Got it right away. Slightly tricky, but really obvious.

  6. I see an answer that moves a numeral, and another answer that moves a line.

  7. Adrian says:

    Took about 15 seconds.

  8. Susqueda says:

    I had to think small, so to speak.

    • Yat says:

      Thank you for pointing out that “move a numeral” is not very accurate. If we just move it, the equation will look to me like one digit is misplaced.

  9. Rachel Mills (@RachelLizMills) says:

    Yeah, done – about a minute.

  10. Timdifano says:

    Done in a couple of minutes.

  11. Gib says:

    1.5 minutes.

  12. ivan says:

    Couple of minutes before inspiration arrived.

  13. Jon says:

    30 seconds…

    The question is flawed, it should be: “Can you move one numeral in the following equation and make the new equation correct?” Nothing you do will make the equation as shown correct.

    I really am surprised at how often these puzzles contain such errors and anomalies, maybe it’s time to stop reading them – certainly not a good advert for buying the book of puzzles.

    • Berhard says:

      yes… and no… under the condition “(mod 2)” the above equation would be correct…

    • Roland says:

      Reminds me of the wife who asked her mathematician’s husband to “buy a bottle of milk at the supermarket”. “And if they have eggs, buy six of them”.

      Her husband returned with six bottles of milk…

      But I had the answer to Richard’s question in about 1 minute 😉

    • Dave's Neighbour's Mum says:

      You must be a blast at parties, Jon.

    • Rushda says:

      But you can’t just move it, it doesn’t look right if it’s not changed/

  14. Ben says:

    Took about 30 seconds.

  15. Eddie says:

    Couldn’t do it so had to read the comments – now got it. Took 35 mins.

  16. Artisticanne says:

    2 min (approx.) before light bulb switched on – my brain obviously not working this morning – should have read Susqueda’s comment first.

  17. Béranger says:

    If you write it in Notepad, using a US keyboard with no extra characters (and no ALT+0xxx tricks), it can’t be done.
    If written using a classic typewriter, “move” involves moving the paper too.
    Indeed, thinking “small”, like Susqueda said, is the problem. Because, technically, the solution is incorrect — it’s only correct for kids.

    • mittfh says:

      I was puzzled until I saw your answer, then I finally got what the “think small” comments were about 🙂

      Meanwhile, in some word processors, a control key combination will do the trick, while in Linux, Alt Gr is your friend…

  18. Yat says:

    I think you will be disappointed.

  19. luke says:

    Just think of it as ‘moving further away’… 😉

  20. -M- says:

    In my handwriting “moving” would suffice 🙂

  21. Calgacus says:

    Not sure where you guys are going with this “changing the size of the numeral” thing. The most straightforward solution solution just moves it.

  22. lamanga2004 says:

    Please disable comments Richard. Every time I come to your page, some idiot has spoiled the puzzle in the first 2 or 3 comments.

    • L Beau says:

      Here’s a new puzzle for you:
      If you want the comment section removed because reading it always spoils the puzzle, should you…
      a) Keep reading the comments anyway.
      b) Just stop reading the comments.

      (SPOILER: The answer is b)

    • mikekoz68 says:

      Seriously? Then y do you come to the comments page? I couldn’t come up with the answer so I came here looking for a hint and I got one from V. Nigel that allowed me to figure out the answer in a few seconds. Try the puzzle from “L Beau”

  23. The Masked Twit says:

    Good puzzle
    Didn’t get it – so Googled it (hope it doesn’t give them any revenue).
    When I saw the answer I was disappointed with myself – I should have thought outside the envelope or pushed the box a bit more. It was low hanging vegetables really, not that I wish to boil the sea.

  24. Anonymous says:

    Cha cha gave me the answer…

  25. Ian says:

    Clever one, Richard, thanks for that 🙂 Took about a minute or so for the penny to drop. Thanks for another pleasant brain workout for the weekend 🙂

  26. Good puzzle this week, because it wasn’t immediately obvious (as most of the puzzles have been recently). I wouldn’t have got it without reading the spoilers in the thread, and I realised it’s just as fun to read the spoilers as not doing.

  27. OccamShave says:


    (For once I can say that. Yay for me!)

  28. Jerry996 says:

    I got it in about a minute or two.

  29. Lazy T says:

    I got a couple of dodgy answers and then a satisfactory one in a couple of minutes, reading the comments confirmed it. Hooray for the ‘cryptic’ spoilers!

  30. One Eyed Jack says:

    Weak sauce again, Richard…. very weak.

  31. Cz-David says:

    First thing that occurred to me is … what are you talking about? This equation is already correct in mod 2…

  32. Daryl says:

    My dream retirement just includes that I am able bodied enough to enjoy it. I suppose I’d just like to live by water.

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