If $n(U)$ = $600$ , $n(A)$ = $100$ , $n(B)$ = $200$ and $n(A \cap B )$ = $50$, then $n(\bar A \cap \bar B )$ is
($U$ is universal set and $A$ and $B$ are subsets of $U$)
Fill in the blanks to make each of the following a true statement :
${{\mathop{\rm U}\nolimits} ^\prime } \cap A = \ldots $
Taking the set of natural numbers as the universal set, write down the complements of the following sets:
$\{ x:x$ is a natural number divisible by $ 3 $ and $5\} $
Let $U=\{1,2,3,4,5,6,7,8,9\}, A=\{1,2,3,4\}, B=\{2,4,6,8\}$ and $C=\{3,4,5,6\} .$ Find
$(A \cup C)^{\prime}$
Taking the set of natural numbers as the universal set, write down the complements of the following sets:
$\{ x:x$ is a perfect square $\} $