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, 2014

Algebra Difficulty 1.4 Junior Find the answer Canada

In the special square shown, the sum of the three numbers in each column equals the sum of the three numbers in each row.

13
8

14
$x$
10

The value of $x$ is

Pick one

Solution

The sum of the three numbers in the first column is $13+14+9=36$ .

The sum of the numbers in each column and in each row in the square is the same and so the sum of the three numbers in the second row is also 36.
That is, $14+x+10=36$ or $x+24=36$ , and so $x=36-24=12$ .

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.