MATH SOLVE

5 months ago

Q:
# If n(A-B)=18,n(AuB)=70 and n(AnB)=25 then find n(B)

Accepted Solution

A:

n(A-B) denotes elements which are in A but not in B n(Au B) denotes elements in A and Bn(AnB) denotes elements that are common in A and B Now I will add one more set n(B-A) which denotes elements in B but not in A So, n(AuB) = n(A-B) + n( B-A) +n(AnB) 70 = 18 +n(B-A) + 2570 = 43 + n(B-A)n(B-A) = 70-43n(B-A) = 27 So, n(B) = n( B-A) + n( AnB)= 27+25= 52