Let A and B be sets in a universe,
with |A ∩ B| = 4
|A U B| = 7
Determine the number of subsets in A U B which contains A ∩ B.
|AUB| = |A| + |B| - |A∩B|
However i think it contradicts the given |A U B| = 7 ,which what i compute = 3.
Also i dont understand what it means by Determine the number of subsets in A U B which contains A ∩ B?? dosent AUB contains A ∩ B arleady?Please enlighten me on how should i solve this question.. thanks