If n(U)=360, n(A)=240, n(B)=160, find the maximum value of n(A union B ) and minimum value of n(A intersection B) . When will be the value of n(A intersection B) be maximum and find its value
We know
n(AUB) = n(A)+n(B)-n(A∩B) 1)
From the formula it is clear that AUB will be maximum when A∩B is least
Now in this question AUB max will be when
AUB=U
This implies max n(AUB) = 360
Now when AUB is maximum A∩B is least
Substituting value of AUB in 1)
360=240+160-n(A∩B)
Hence solving we get
Min value of A∩B =40
Similarly max value of A∩B is when B is a subset of A
Hence A∩B maximum=n(B)=160
Hope it helps!!!