Answer:
2:5
Step-by-step explanation:
The ratio of a dimension on Figure B to the corresponding dimension on Figure A is ...
4:10 = 8.6:21.5 = 10:25 = 2:5 or 1:2.5
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In such problems, it isn't clear if the desired answer is the ratio of two integers or if it is 1 : (something). We have expressed it both ways, so you can use the answer that matches your requirement.