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## Question

So, try to figure out which one of the 9 possibilities given is the correct one. Give the method you used and explanation to see if it is the same one I used.

## 26 answers to this question

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That it is either B or E because all of the others are in pairs except those matching to B and E

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further narrowing it down to b--it has an "opposite" piece, e is centered and therefore doesn't

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I believe the answer is A, because you duplicate the puzzle and put it edge to edge the squares follow a pattern. if you build one unified puzzle with the numbers in it for the dark squares. The numbers follow the pattern 5,1,1,5,11,5,11,5

I believe the answer is A, because you duplicate the puzzle and put it edge to edge the squares follow a pattern.

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Any of B,D,F, or H, as rotations of any of these together with rotations of the 8 given, will, when superimposed, make a black 3 by 3 grid. This is one of many equally valid answers to this problem!

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You are getting close. However that is not the answer . Here's another one, which is a little bit harder than the previous one. Have fun with it!

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According to me its 'e'

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E

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H

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H

Reasoning?

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Assigning values 1-9 (starting at the top and reading left to right as in the labeled square above), take the sum of the values of each column from bottom to top mod 10.

So for column 1: A1 + B1 = C1 (mod 10) or 7 + 1 = 8 and 8 mod(10) = 8; column 2: 8 + 7 = 15 and 15 mod(10) = 5

Then ? + 2 = 1 so ? = 9 giving i as an answer.

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This is for the original puzzle...

First, given that the eight 3x3 grids can be numbered left-to-right and top-to-bottom as 1 through 8 with the missing item being number 9, and given that each 3x3 grid can similarly have its 9 squares numbered so that the top-left is "1" and the bottom-right is "9"...

Assume that the top row of grids are to be rotated 90 degrees clockwise, the middle row are not rotated, and the bottom row are rotated 90 degrees counter-clockwise. The top row grids' black spots would then occupy positions 4, 5, and 3. The middle row grids' blacks spots occupy positions 1, 7, and 2. The bottom row grids' blacks spots would occupy positions 9 and 6, leaving position 8 to be filled. To fill position 8 after a CCW rotation, we need grid "D" from the possible answers.

My answer is "D".

I tried a number of other revolving algorithms but they always resulted in at least one duplicate.

And if this is correct, I owe it to those who answered before me. I did not see this approach to a solution on my first three reads of the OP.

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Assigning values 1-9 (starting at the top and reading left to right as in the labeled square above), take the sum of the values of each column from bottom to top mod 10.

So for column 1: A1 + B1 = C1 (mod 10) or 7 + 1 = 8 and 8 mod(10) = 8; column 2: 8 + 7 = 15 and 15 mod(10) = 5

Then ? + 2 = 1 so ? = 9 giving i as an answer.

plainglazed, that was deep. I don't know if it's correct, but either way, nice work.

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i think it's F

if you assign a numerical value to each square 1, 2, 3 (top row), 4, 5, 6 (middle row) and so on, and then make a chart of where the black squares are, you'll notice the following mathematical pattern:

the SUMS of each row and column (when added together with its "brother" is 30)

for example Row 1 + Column 1 = 30

Row 2 + Column 2 = 30

So, using algebra or trial and error, etc, you can figure out that the missing value for the 9th square must be SIX in order for row 3 and column 3 to add up to 30

here's how it looks, the numbers represent where the black squares are:

8 5 1 = 14

1 7 2 = 10

7 8 X = ??

16 * 20 * ??

16 + 14 = 30 (column 1 total + row 1 total)

20 + 10 = 30 (column 2 total + row 2 total)

(3 + X) + (15 + X) = 30

X = 6

so, pattern 6 is Row 2, Column 3 = F Pattern

get there....

Reasoning?

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So, try to figure out which one of the 9 possibilities given is the correct one. Give the method you used and explanation to see if it is the same one I used.

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i think it is D because if we merge all blocks all smaller blocks in first row blocks come 2 times

in third row blocks come 2 times

and if we select option 'D', middle row blocks we come once.

so a pattern is being formed if we select option 'D'.

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For the first puzzle, it's i...2+5=7, 1+7=8 and 1+2=3.

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For the second it's h, green squares have to have red and white squares on the same square location in the other grids within the sam row and column.

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Makes sense, but wouldn't a simpler solution be assigning it 1-9, but starting from the bottom left square? Bottom left square is 1 and top right square is 9. So the first row it's 2+5=7, 2nd row it's 1+7=8 and last row is simply 1+2=3.

Assigning values 1-9 (starting at the top and reading left to right as in the labeled square above), take the sum of the values of each column from bottom to top mod 10.

So for column 1: A1 + B1 = C1 (mod 10) or 7 + 1 = 8 and 8 mod(10) = 8; column 2: 8 + 7 = 15 and 15 mod(10) = 5

Then ? + 2 = 1 so ? = 9 giving i as an answer.

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Makes sense, but wouldn't a simpler solution be assigning it 1-9, but starting from the bottom left square? Bottom left square is 1 and top right square is 9. So the first row it's 2+5=7, 2nd row it's 1+7=8 and last row is simply 1+2=3.

Frederico1, your solution is novel and valid, but I would not disagree with plainglazed's solution. It is also a novel and valid solution, even if it is a more complex approach. Lacking any clear direction from FoodForThought up to this point, both are reasonable and logical.

While I appreciate your solution I think that in the final analysis it will not be chosen as "correct" by FoodForThought because your approach to the "numbering" of the squares in the grid is counter to the ordinal positions ascribed by the originator of the puzzles - notice which solution is labeled "A" and which is labeled "I". This is just opinion, but I think that a person who would start at "A" at the top-left would also start at "1" for that position.

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'E'

because first thing i noticed was that all the shades are among 'a','b','e','g' and 'h' so the answer must be one of them and second thing if you see you will notice that in a single row or column a shade is not repeating its place so in the 3rd column chances of 'a' and 'b' are over and in the 3rd row 'g' and 'h' are canceled so the remaining 'e' must be the answer

The shades in the 2nd row overlaps the shades in the first row at only 1 point and similarly the shades in the 3rd row overlaps the shades in the 2nd row at only one point

SORRY if i am not able to explain but you can see at the attachment

Edited by Shivam

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1st Puzzle. I agree with Fredrico1, the answer must be... ]I. If the squares are assigned numerical values as follows:

789

456

123

- then we get 3 simple addition sums.

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In my opinion, the answer to the first puzzle is B.

Reasoning is simple: All pieces need to have a symmetrical counter piece ( the symmetri axe is the horizontal middle row ).

You got 3 pieces that repeat 2 times. if you check it 2 of those pieces respect the symmetry line. the other piece that is double has just 1 symmetrical counter part, and that is the B answer.

The last piece, the one with the DOT in the middle, is it's own symmetrical counterpart , and for the sake of logic in that picture, the one piece that is missing is B

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to the 1st puzzle, could it be that if we were to number the box, we will arrive at (8 5 1) , (1 7 2) and ( 7 8 x)

we then take the leap of faith that the connection between the 3 digits are a decreasing sum. 8 + 7 = 15, 15 + 6 = 21

we then eliminate the ten digits from each sum. leaving behind 8 5 1

for row 2, we have 1 + 6 = 7, 7 + 5 = 12

as for the last row, we get 7 + 9 = 18, 18 + 8 = 24

and thats how i arrived at option D

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I think it is E, the way I see it the pairs line up like Chess Knight moves. They make an L shape.

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c

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