ohmygyatt wait, I kind of managed to solve it.
Draw a venn diagram. One side for A, one side for B
B only aka (A' and B) = 2. So put 2 in circle B
Next, the question states that there are 3 elements that are neither A, nor B. Therefore, n(A' and B') would not be in any of the circles of the venn diagram. they stay outside.
I've got some exams tomorrow and that's all I got to solve rn but if I manage to solve the whole thing I'll add it here
