How to do this simple set operation?

Question

Suppose A and B are events with P(A) 0.4 , P(B) 0.6 and P(A and B) 0.25 . Calculate the probability P(A complement union B).

A 0.25

B 0.65

C 0.75

D 0.85

What I tried?-

P(A union B)=P(A)+p(B)-P(A and B) i.e=0.4+0.6-0.25=0.75. I am stuck after this. i know this is simple but I am unable to find the right approach.

Below is the diagram that I created after solving up to here.

Answer 1

Your graph is fine. Now you can mark the area of $\overline A$. I did this with red lines. It is just the whole rectangle without $A$.

After that you mark the area of $B$

I did this with blue lines.

Now the union of this two areas are the whole rectangle without the unmarked area. Because of the values you already have inserted it can be easily seen (calculated) what $P(\overline A \cup B)$ is.