Question

If n (A) = 15 ,n ( A U B ) = 29 , n ( A ∩ B ) = 7 then find n ( B ) ?

Answer 1

Answer:

n(B)=21

Step-by-step explanation:

n(A U B)=n(A)+n(B)-n(A∩B)

29=15+n(B)-7

29=8+n(B)

29-8=n(B)

21=n(B)

Answer 2

Answer:

n(b)=21

Step-by-step explanation:

n(a 4 b)=n(a)+n(b-n(anb)

29=15+n(b)-7

29=8+n(b)

29-8+n(b)

21=n(b)