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Algebra Difficulty 1.2 Junior Find the answer Canada

The equal-arm scale shown is balanced.

One has the same mass as

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solutions — 3

Solution 1

The equal-arm balance shows that 2 rectangles have the same mass as 6 circles.
If we organize these shapes into two equal piles on both sides of the balance, then we see that 1 rectangle has the same mass as 3 circles.

Solution 2

The equal-arm scale shows that $2$ squares have the same mass as $4$ circles.

If we split the $2$ squares and the
$4$ circles each into two equal
groups, then $1$ square has the same
mass as $2$ circles.

Solution 3

The length of the side not labelled is equal to the sum of the two horizontal lengths that are labelled, or $2+3=5$ . Thus, the perimeter of the figure shown is $5+5+2+3+3+2=20$ .

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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.