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
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
If S \(\subset\) T \(\subset\) W,
S \(\cap\) T \(\cap\) W = S is true since S \(\cap\) T = S and S \(\cap\) W = S.
S \(\cup\) T \(\cup\) W = W is also true. S \(\cup\) T = T and T \(\cup\) W = W.
However, to say that T \(\cap\) W = S is not very true mathematically. Instead, it is safe to say S \(\subset\) (T \(\cap\) W).
Source: Myschool Past Questions Archive (Record #9313)