The ratio of circle to triangles is; 3:4 and the number of circles which should be added to make the ratio 1:1 is; 3.
It follows from the task content that the total number of circles and triangles in all 4 rows and can be counted and concluded as; 9 and 12 respectively.
Hence, the ratio of circles to triangles is 9 to 12 and in its simplest form is; 3:4.
However, to make the ratio 1:1, the number of circles and triangles must be equal. Hence, 3 circles must be added to make the ratio 1:1.
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