If a mates folder has 10 mates, how would I know which mates are used to keep the assembly in place?
That's an ambiguous question to answer.
There may not be any mates holding the assembly in place, the assembly may be floating.
There may be a single part or sub-assembly that is fixed and all the other stuff is mated to that.
There may be some mates relating to the origin or primary planes, and you would need to look at the mate descriptions to determine which are valid. You can click on them to highlight what they are mating.
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