Question

please answer me in this question ​

Answer 1

Answer:

n (A)=4

n (B)=7

n (A intersection B) =4 because A is subset of B

n (A U B) = n (A) + n (B) - n(A intersection B)

n (A U B) = 4+ 7- 4 = 7

May be 7 is right answer.