Question

73. If n(A) = 115, n(B) = 326, n(A - B) = 47, then
n(A U B) is equal to
(a) 373 (b) 165 (c) 370 (d) 389​

Answer 1

Answer:

373

Step-by-step explanation:

n(AuB)=n(A)+n(B)-n(AnB)

n(AnB) =n(A)-n(A-B)=68

so n(AuB)= 373

Answer 2

Answer:

Step-by-step explanation:

Given,

n(A) = 115

n( B) = 326

n(A-B) = 47

Here, n(A∩B) = n(A)-n(A-B)

          n(A∩B) = 115 -47

          n(A∩B) = 68

n(AUB) = n(A) + n(B) -n(A-B)

            = 115 + 326 - 68

n(AUB)  =373