N(A) = 75 = p+x
N(B) = 35 = x+q
n(E) = 200 = p+x+q+y
(i)find the smallest possible value of y where y is (AUB)'
That'll be when there's the most possible in the two circles,
which is when their intersection x is the least, or when
x=0, p=75, q=35, and y=90 (that's also when p and q are the
most they can be, and x is the least it can be.)
(ii)the largest possible value of x where x is AnB.
That'll be when all of B is in x which is when q=0,
x=35, p=40, and y=125. (That's also when y is the most
it can be, and when p and q are the least they can be)
(iii) find the value of of q if p= 45
That'll be when x=30, q=5, and y=120.
Edwin