Question 148032
U = {18. 19. 20, 21, 22, 23, 24, 25, 26, 27, 28, 29}
A = {21, 23, 25, 27, 29}
B = {26, 27, 28, 29}.

A`={18,19,20,22,24,26,28}
B`={18,19,20,21,22,23,24,25}
then
A`UB`={18,19,20,21,22,23,24,25,26,28}

U = {l, m, n, o, p, q, r, s, t, u, v, w}
A = {l, m, n, o, p, q}
B = {n, o, r, s, v, w}  
C = {l, m, p, q, r, t}
 find (A′ U C′) ∩ B′. 

A`={r,s,t,u,v,w}
C`={n,o,s,u,v,w}
A`UC`={n,o,r,s,t,u,v,w}
B`={l,m,p,q,t,u}
(A′ U C′) ∩ B′={t,u}

#(KUJ)=#(K)+#(J)-#(K∩J)=30+46-11=65