<PRE><B>Question 1050706</B>
i get B = 37.


the formula to use is:


(A or B) = A + B - (A and B).


you are given that (A or B) = 90
you are given that A = 86
you are given that (A and B) = 33


the formula becomes:


90 = 86 + B - 33


simplify to get 90 = B + 53


subtract 53 from both sides of the equation to get:


B = 90 - 53 = 37.


there are 86 elements in A.
there are 37 elements in B.
there are 33 elements that are in both A and B.


there are 86 - 33 = 53 elements that are in A only.
there are 37 - 33 = 4 elements that are in B only.
there are 33 elements that are in both A and B.


the total elements are 53 + 4 + 33 = 90.


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