Question 250171
1. Set X = {5, 7, 11, 13, 16,19}, Set Y = {1, 2, 5, 13, 19}
a. What is the union of Sets X and Y? 
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If an element is a member of X, or is a member of Y, 
or is a member of both X and Y, then it is a member 
of the union of sets X and Y. 

So the union of X and Y is this set:

{1, 2, 5, 7, 11, 13, 16, 19}
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b. What is the intersection of Sets X and Y 
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For an element to be a member of the intersection 
it must be both a member of X and also a member of Y.
(Intersection is more restrictive than union.)

So the intersection of sets X and Y is this set:

{5, 13, 19}}}
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c. Create your own set Z that is a subset of Set X.
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Set Z can be any of these.  Take your pick:

{ }
(5}
{7)
{11}
{13}
{16}
{19}
{5, 7}
{5, 11}
{5, 13}
{5, 16}
{5, 19}
{7, 11}
{7, 13}
{7, 16}
{7, 19}
{11, 13}
{11, 16}
{11, 19}
{13, 16}
{13, 19}
{16, 19}
{5, 7, 11}
{5, 7, 13}
{5, 7, 16}
{5, 7, 19}
{5, 11, 13}
{5, 11, 16}
{5, 11, 19}
{5, 13, 16}
{5, 13, 19}
{5, 16, 19}
{7, 11, 13}
{7, 11, 16}
{7, 11, 19}
{7, 13, 16}
{7, 13, 19}
{7, 16, 19}
{11, 13, 16}
{11, 13, 19}
{11, 16, 19}
{13, 16, 19}
{5, 7, 11, 13}
{5, 7, 11, 16}
{5, 7, 11, 19}
{5, 7, 13, 16}
{5, 7, 13, 19}
{5, 7, 16, 19}
{5, 11, 13, 16}
{5, 11, 13, 19}
{5, 11, 16, 19}
{5, 13, 16, 19}
{7, 11, 13, 16}
{7, 11, 13, 19}
{7, 11, 16, 19}
{7, 13, 16, 19}
{11, 13, 16, 19}
{5, 7, 11, 13, 16}
{5, 7, 11, 13, 19}
{5, 7, 11, 16, 19}
{5, 7, 13, 16, 19}
{5, 11, 13, 16, 19}
{7, 11, 13, 16, 19}
{5, 7, 11, 13, 16, 19}

Edwin</pre>