what do you mean by.... (elementary algebra)

Question

There are 4 circles A,B,C & U representing sets, 3 of them (A,B,C) intersecting each other.... A is set of red objects, B is set of blue and C is set of yellow.... U is said to be a universal set.. U circle is in the isolation of the other 3 intersecting none.... Draw a Venn diagram.... { I've got a pretty good idea about A,B,C but cannot understand the position of U in the diagram and what do ' in isolation of other 3 intersecting none means'....??}

Answer 1

I presume this is related to a previous question and answer of mine.

This is the Venn diagram:

The sets A, B and C interlock but alpha is isolated. The questions asks what U is, and I would say that the universal set is the paper on which the diagram is drawn because it contains all sets.

Comments

Well the question is completely different but is similar to one of my earlier... And coz of this... I think my other Venn diagram is incorrect as I placed U in the intersection coz technically it won't be intersecting any but contained in all 3... And what does isolation means here...??

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Yes, definitely similar. You could draw U as a big circle containing the other four. U can't, by definition, be contained. Isolation means not connected to anything else. So the set alpha is a subset of U but does not intersect with A, B or C. A is red objects, B blue objects and C yellow. Where the sets overlap we have a set of red and blue objects, red and yellow objects, blue and yellow objects and a set of red, blue and yellow objects. An isolated set would be, for example green objects. U would be objects of all colours, for example. A, B, C and alpha are all subsets of U. (I'm assuming U is the universal set.)