Find the missing number in these grids. I was unable to find any pattern.
Choices:
- 9
- 6
- 8
- 4
source: Borhan Motevasete magazine, Oct. 2007
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Sign up to join this communityFind the missing number in these grids. I was unable to find any pattern.
Choices:
source: Borhan Motevasete magazine, Oct. 2007
Edit: Changed the reasoning based on Jaap Scherphuis's comment as it seems more natural.
I think the answer is
$6$
Reasoning
Add the numbers in the lower four boxes and take the absolute difference between the digits in the result to the get the number at the top (Originally: take the residue modulo $11$ to get the number at the top)
Examples
$4+1+6+3 = 14 \rightarrow |1-4| = 3$
$9+2+7+8 = 26 \rightarrow |2-6| = 4$
$3+1+8+5 = 17 \rightarrow |1-7| = 6$