Question

set X has x+2b members and set Y has y+3b members. if they have exactly b members in common, how many elements are in the union of X and Y but not in the intersection of X and Y?
a. x+y
b. x+y+3b
c. x+y+4b
d. x+y+5b
e. x+y+6b

Answer 1

hint: the formula you need is found on this page

http://math.stackexchange.com/questions/398809/cardinality-of-intersection-of-sets