Page 23 - 091math-wb-w3-(sets)

WORKBOOK

Example 15: Find n(B) if n(A  B) = 4, n(A  B)=18 and n(A) - n(B)=6 .

Example 16: A and B are two sets. n(A)=13 and n(B) = 8

a) What is n(A  B) at least?

b) What is n(A  B) at most?

Example 17: () = 32, () = 19,() = 25,( ∪ ∪ ) = 54 and
4( ∩ ) = 3( ∩ ) = 2( ∩ ) = 6( ∩ ∩ ) are given. Find ( ∩ ∩ )

*NOTE: ( ∪ ∪ ) = () + () + () − ( ∩ ) − ( ∩ ) − ( ∩ ) + ( ∩ ∩ )

Example 18: Determine whether each of the following propositions true or false.

I) A and B are two sets; ( ∪ ) ≤ () + () :………………

II) A and B are two sets; If ⊂ then ∪ = :………………

III) A and B are two sets; ⊂ ( ∪ ) and ⊂ ( ∪ ) :…………….

IV) A and B are disjoint sets; ( ∪ ) = () + () :……………….

23 091math-wb-w3-(sets)