One equivalent ratio is 1:6
To get this ratio, you divide both parts of 2:12 by 2
2/2 = 1
12/2 = 6
So that's why 2:12 is equivalent to 1:6
From here we could multiply both parts by say 3
1*3 = 3
6*3 = 18
Meaning that 1:6 and 2:12 are equivalent to 3:18
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Two possible answers are 1:6 and 3:18
There are infinitely possible answers