SETS 1

If n(A)= 60 , n(AuB) = 200 and n(AnB)=20, find n(B)

Solution

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

  200     = 60 + n(B)  – 20

  200     = 60 -20 + n(B) 

  200     = 40 + n(B) 

  200 - 40        = n(B)

  160        = n(B)

Hence n(B) = 160 answer

TRY THIS…………………………….

If n(A)= 68 , n(AuB) = 127 and n(AnB) = 25, find n(B).