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CEMC Gauss (Grade 7), 2016

Geometry Difficulty 1.4 Junior Find the answer Canada

The diagram shown contains octagons and squares only.

The ratio of the number of octagons to the number of squares is

Pick one

Solution

In the diagram, there are 4 rows of octagons and each row contains 5 octagons.

Therefore, the total number of octagons in the diagram is $4\times5=20$ .

In the diagram, there are 3 rows of squares and each row contains 4 squares.

Therefore, the total number of squares in the diagram is $3\times4=12$ .

The ratio of the number of octagons to the number of squares is $20:12$ or $5:3$ .

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