Question 11
Each row, column and diagonal of this $3\times3$ grid should add up to 30. What number goes in the bottom-right corner? The given entries are 2 in the top-middle cell, 8 in the middle-left cell and 12 in the middle-right cell.
||2||
|---|---|---|
|8||12|
|||?|
||2||
|---|---|---|
|8||12|
|||?|