SETS 1

If n(A)= 60 , n(AuB) = 100 and n(AnB)=10, find n(B)

Solution

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

  100     = 60 + n(B)  – 10

  100     = 60 -10 + n(B) 

  100     = 50 + n(B) 

  100 - 50        = n(B)

  50        = n(B)

Hence n(B) = 50 answer

TRY THIS…………………………….

If n(A)= 67 , n(AuB) = 110 and n(AnB) = 33, find n(B).