Solution:
(i) (A ∩ B) ∩ (B ∪ C) 
{7, 9, 11} ∩ {7, 9, 11, 13, 15}
{7, 9, 11}
(ii) (A ∪ D) ∩ (B ∪ C) {3, 5, 7, 9, 11, 15, 17) ∩ {7, 9, 11, 13, 15}
{7, 9, 11, 15}
If A {3, 5, 7, 9, 11}, B {7, 9, 11, 13}, C {11, 13, 15} and D {15, 17}; find (i) (A ∩ B) ∩ (B ∪ C) (ii) (A ∪ D) ∩ (B ∪ C)
{3, 5, 7, 9, 11}, B {7, 9, 11, 13}, C {11, 13, 15} and D {15, 17}; find (i) (A ∩ B) ∩ (B ∪ C) (ii) (A ∪ D) ∩ (B ∪ C)