# Use the example of the wages of the group of 10 friends is used to illustrate the above concept.

Use the example of the wages of the group of 10 friends is used to illustrate the above concept.

(i) The universal set, U = {6, 8, 10, 12, 15, 18, 20, 21, 23, 25}

Let A be the set of wages in (N?000) that are at least 11 and at most 21 and B is the set of wages that are above 16, we then have A = {12, 15, 18, 20, 21}

B = {18, 20, 21, 23, 25} Hence by definition,

(ii) AC = {6, 8, 10, 23, 25}

(iii) A B = {12, 15, 18, 20, 21, 23, 25} Note that if we had ordinarily merged A and B, the

elements 18, 20, 21 would have been duplicated.

(iv) A B = {18, 20, 21} These are the elements that are common to both sets. The keyword for Union is OR while AND is for intersection. A B is described in words as A or B, while A B is described as A and B.