
Example: If, n(A) = 7, n(B) = 8 and n(A Ç B) = 3, then find the value of n(A È B). Solution: Ginve that, n(A) = 7, n(B) = 8 and n(A Ç B) = 3. Formula for the above prolblem is n(A È B) = n(A) + n(B)  n(A Ç B). = 7 + 8 3 = 15  3 n(A È B) = 12.
Note: Directions: Choose the correct answer. Also write at least 5 examples of your own. 