SETS J1

 If n(A)= 85 , n(B)= 96 and n(AuB)= 129, find n(AnB).

 

Solution

 

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

 

129 = 85 + 96 - n(AnB)

 

129 = 181 - n(AnB)

 

129 - 181 = - n(AnB)

 

-58 = -n(AnB)

 

n(AnB) = 58 [after dividing by -1 both sides]

 

Hence n(AnB) = 58 answer

 

 

TRY THIS………….

 

 

If n(A)= 91 , n(B)= 94 and n(AuB)= 127, find n(AnB).