SETS 1

If n(A)= 60 , n(AuB) = 140 and n(AnB)=30, find n(B)

Solution

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

  140     = 60 + n(B)  – 30

  140     = 60 -30 + n(B) 

  140     = 30 + n(B) 

  140 - 30        = n(B)

  110        = n(B)

Hence n(B) = 110 answer

TRY THIS…………………………….

If n(A)= 60 , n(AuB) = 134 and n(AnB) = 33, find n(B).