Question

If n(A-B)=35-x ,n(B-A)=30-x ,n(A ∩ B)= x ,n(A U B )=60 ,then x is

a.5 b.6 c.7 d.8
​

Answer 1

Answer:

I don't understand the meaning

Answer 2

Answer:

x=5

Step-by-step explanation:

Given,

n(A-B)=35-x ,n(B-A)=30-x ,n(A ∩ B)= x ,n(A U B )=60

Then,

n(A U B ) = n(A-B) + n(B-A) + n(A ∩ B)

or, 60 = 35 - x + 30 - x + x

or, 60 = 65 - x

or, x = 65 - 60

i.e. x = 5