A union B consists of all those that are in set A as well as all those that are in set B (just don't count
anyone twice: 8, 14, 17, 16, 9, 15.
A intersect B consists of only those which are in the overlap of A and B (14, 17 ).
A' consists of all the numbers that aren't in A (16, 9, 15, 13, 10, 11, 12)
The probability of randomly choosing a number that is in A' is the number in A divided by the total
number of numbers; you can do this!
Question #2: X' inersect y'
-- the area cannot contain any of circle X and cannot contain any of circle Y
-- which picture leaves all of circle X and all of circle Y unshaded?