There are two answers
choice A 3:1
choice B 9:3
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Explanation:
Note how 27 and 9 have a common factor of 3.
Divide each part by this common factor
27/3 = 9
9/3 = 3
So 27:9 is equivalent to 9:3
Choice B is one of the answers
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Another common factor of 27 and 9 is 9. This is the greatest common factor (GCF). Divide both parts by the GCF
27/9 = 3
9/9 = 1
The ratio 27:9 is equivalent to 3:1
Choice A is one of the answers
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Another way to see why choice A and choice B are the answers is to divide the two parts of the original ratio from left to right
27/9 = 3
Then for choice A's ratio of 3:1, we do the same to get 3/1 = 3
and choice B as well to get 9/3 = 3
Each time we divide the parts of teh ratio from left to right, we end up with 3 as a result.
Something like choice C doesn't work because 6/3 = 2 and choice D is 9/6 = 1.5 and choice E is 12/3 = 4, showing all different results from 3.
