The nine white squares inside the main red grid should be filled with the digits 1 through 9. Each digit should appear only once in this main grid. Two of these numbers are already provided for you. Place the other digits in the correct spots so that the mathematical equations work both across and down. IMPORTANT: Remember algebraic rules when solving the problems… multiplication and division should be performed in the first step, then addition and subtraction in the second. Good luck!
Comments (12)
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Sandy – sorry but there seems to be an error in this puzzle. On the second line you have 2 + 1 x 6 = 8 (not 18 as I suspect you wanted it). That makes the puzzle a lot harder!
posted by Jane on 6-28-2010 at 10:52 am
Damn that pemdas!
posted by Mike on 6-28-2010 at 11:05 am
Jane, the puzzle’s right. Following the order of operations …
2 + 1 x 6
2 + (1 x 6)
2 + 6
8
Multiplication and division first, addition and substraction second.
posted by Joe on 6-28-2010 at 11:33 am
Sandy, not sure if you can make the caveat any bolder but people still continue to miss your explicit instructions. At what point do you quit laughing and just shake your head?
posted by Brad on 6-28-2010 at 11:59 am
Maybe there should be a link to order the “Please Excuse my Dear Aunt Sally” t-shirt. :-)
posted by Eric on 6-28-2010 at 12:38 pm
Sandy, I recall a comments conversation regarding the difficulty of the puzzle and the correlation to Mondays being the day we get our math squares. Have you thought of maybe having every 5th or 10th square just ratchet up the difficulty something fierce? Just a thought.
Love these!
posted by Tim on 6-28-2010 at 12:51 pm
I can’t click on the form. How am I supposed to work this out?
posted by RonNasty64 on 6-28-2010 at 1:16 pm
RonNasty64, try this somewhat unique method. Use something called paper and pencil.
posted by Brad on 6-28-2010 at 1:34 pm
My favorite part of these puzzles is checking the comments to see who couldn’t follow directions.
I’ll admit it: it gives me a little smug sense of satisfaction every time. Don’t change a thing.
posted by B on 6-28-2010 at 1:58 pm
if we assume the puzzle in the form:
abc
def
ghi,
Then,
(1) ab-8=19, ab=27
a,b are in the set (3,9)(9,3)
(2)d+ef=8
(3)g+4-i=2, i-g=2
g,i are in the set (4,6)(5,7)(6,8)
(4) a-d+g=12
(5) b+e-4=0, b+e=4
b,e are in the set (1,3)(3,1)
by (1), we know that b=3
Therefore a=9 and e=1
(2) becomes d+f=8
d,f are in the set (2,6)(6,2)
(4) becomes 9-d+g=12, g-d=3
d,g are in the set (2,5)(6,8)
Since g=5 or 8, by (3), we know it must be 5, therefore d=2, i=7, and f=6
938
216
547
posted by Izzy on 6-28-2010 at 2:17 pm
Maybe there should be instructions which politely ask people not to post solutions in the comments. (Then again, if nobody reads the instructions, we’ll still get people posting solutions. Alas.)
posted by Dinosaur on 6-28-2010 at 3:51 pm
Following the order of operations was harder for me in this one because of the middle line. I know multiplication comes first, but I since read right to left, I saw the plus sign first, and my brain kept adding before multiplying. It’s easy to get confused, even if you know the correct way to do it!
posted by Grobanite33 on 7-2-2010 at 4:24 pm