The upside down U means the numbers the sets have in common.
Do what is in parenthesis first:
(B ∩ C) = 6 is the only common number in set B and Set C.
A ∩ (B ∩ C) = Would be all the numbers in A plus the number 6 from (B ∩ C).
The answer would be A) {1, 3, 5, 6, 7, 9}
1546/12 = 128.3333333333333333333333333333333333333
It should be 270 since 6 x 9 x 10 x 1/2= 270
42
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