I.S∩T∩W=S II. S ∪ T ∪ W = W
III. T ∩ W = S
If S⊂T⊂W, which of the above statements are true?
A.
I and II
B.
I and III
C.
II and III
D.
I, II and III
Correct Answer: I and II
Explanation
If S ⊂ T ⊂ W,
S ∩ T ∩ W = S is true since S ∩ T = S and S ∩ W = S.
S ∪ T ∪ W = W is also true. S ∪ T = T and T ∪ W = W.
However, to say that T ∩ W = S is not very true mathematically. Instead, it is safe to say S ⊂ (T ∩ W).
If S ⊂ T ⊂ W,
S ∩ T ∩ W = S is true since S ∩ T = S and S ∩ W = S.
S ∪ T ∪ W = W is also true. S ∪ T = T and T ∪ W = W.
However, to say that T ∩ W = S is not very true mathematically. Instead, it is safe to say S ⊂ (T ∩ W).
