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                  | Question 1
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                  | A = {2, 4, 6, 8}, B =  {2, 3, 7, 9} and C = {x: 3 < x < 9} are subsets of  the universal-set U = {2, 3, 4, 5, 6,  7, 8, 9}. Find
 (a)   A n(B'nC');
 (b)  (AuB) n(BuC).
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                    This question was  reportedly attempted by majority of the candidates and their performance 
                      was described as satisfactory. Many of them lost some marks because they failed  to use curly 
                      brackets to enclose the elements of the sets. A good  number of the candidates were also 
                      reported not to have listed the elements of set C hence, were not able to find its complement 
                      while others did not separate the elements of a set with comas.   Candidates were expected  to list the elements of C i.e. C = {4, 5,6, 7, 8}, obtain the compliments 
                      of the sets Band C thus B' =  {4,5,6, 8}, C' = {2, 3, 9,}. Using these sets, the following procedures 
                      were to be followed: (a)(B' nC') = { } Hence An (B' n C') = { }. Some  candidates were reported to have 
                      written { 0 } instead of { } or 0.
 (b)  (A u B)  = { 2, 3,4,6, 7, 8, 9 }, (BuC) = {2, 3,  4,5,6, 7, 8, 9 } 
                      Therefore { Au B } n (BuC) = { 2, 3, 4, 6, 7, 8, 9 }.
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