Eric Nicholas K's answer to holowinwin's Secondary 4 E Maths Singapore question.
For (iv) also possible is
B u C (3, 4, 5, 6, 7, 8)
intersect A' (killing the 5, 7 and 8)
intersect B (killing the 4, so keeping only the 3 and 6).
B u C (3, 4, 5, 6, 7, 8)
intersect A' (killing the 5, 7 and 8)
intersect B (killing the 4, so keeping only the 3 and 6).
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