Answer is 2:15
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Explanation:
The ratio of WX:XY is given to be 2:1. Let's double each part to get 4:2. Those two parts add to 4+2 = 6.
The ratio WY:YZ is 2:5. If we triple each part, then we get 6:15. The '6' here matches from the 6 we found earlier.
So the WX+XY = 4+2 = 6 matches with the WY = 6 in the second ratio. This means XY:YZ = 2:15
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Check out the diagram below. It represents a visual way to see how we got the answer. I'm using boxes to represent each smallest unit or part. Chaining together boxes forms the lines or curves. The WX portion is in blue consisting of 4 parts, XY is in green (2 parts), and YZ is in orange (15 parts).
The diagram shows that WX:XY = 4:2 = 2:1, and that WY:YZ = 6:15 = 2:5
Furthermore, it shows that XY:YZ = 2:15
