How would you describe in words (X'U Y')U Z?Let X={a,b,c} Y={a,c,e,g} Z={b,c,d,e,f}
You provide good information here. Also note for the future that a well-posed questions explains what you do and do not understand about the situation.
(X' U Y ' ) U Z is the set of all elements that lie outside of X, or outside of Y, or within Z.
The exact listing of these sets would depend on the universal set, but it would have to include all the elements b, c, d, e, f of A as well as everything in the universal set that lies outside of X, as well as everything in the universal set that lies outside of Y.