Question 1059707
it looks like what you have is:


1,3,5,7,9 belong to the universe.


1,3,5,9 belong to A.


1,9 belong to B.


5 belongs to C.


all of the elements in A are part of the universe, except for 7.


all of the elements in B are part of A, except for 3,5.


all of the elements in C are part of A except for 1,3,9.


what this says is:


A is a proper subset of the universe.
B is a proper subset of A.
C is a proper subset of A.
there are no elements in B that are common to C.


if I had to draw a venn diagram of this, i would probably draw the following:


<img src = "http://theo.x10hosting.com/2016/120201.jpg" alt="$$$" </>


you can see that B and C have no common intersections between them.


you can see that B and C are wholly contained in A.


you can see that A is wholly contained in the universe.


you can see that 7 is not part of any of the subsets of A, B, and C.


if i had to draw a 3 ring venn diagram, i would probably do the following:


<img src = "http://theo.x10hosting.com/2016/120202.jpg" alt = "$$$" </>


you can see that A is wholly contained in the universe.


therefore A is a proper subset of the universe.


you can see that 7 is in the universe, but not part A, B, or C.


you can see that B and C have no elements that are not common to A.


you can see that 1 and 9 are part of both A and B.


you can see that 5 is part of A and B.


you can see that there are no elements that are common to A, B, and C.


I think the first diagram probably depicts the situation better than the second diagram.


it visually represents what the situation is all about.


the universe contains 1,3,5,7,9
A contains 1,3,5,9
B contains 1,9
C contains 5


A is a proper subset of the universe.
B is a proper subset of A.
C is a proper subset of A.



here's a reference that might be helpful.
http://www.mathsisfun.com/sets/