If $n(X)=700, n(A)=200, n(B)=300, n(A \cap B)=100$, where $X$ is universal set and $A$ and $\mathrm{B}$ are subsets of $\mathrm{X}$, then $\mathrm{n}\left(\mathrm{A}^{\prime} \cap \mathrm{B}^{\prime}\right)=$

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Aicharya · Accepted Answer

$\mathrm{n}(\mathrm{A} \cap \mathrm{B})=\mathrm{n}(\mathrm{A} \cup \mathrm{B})$ $=\mathrm{n}(\mathrm{u})-\mathrm{n}(\mathrm{A} \cup \mathrm{B})$ $=\mathrm{n}(\mathrm{u})-\{\mathrm{n}(\mathrm{A})+\mathrm{n}(\mathrm{B})-\mathrm{n}(\mathrm{A} \cap \mathrm{B})\}$ $=700-\{200+300-100\}=300$

If $n(X)=700, n(A)=200, n(B)=300, n(A \cap B)=100$, where $X$ is universal set and $A$ and $\mathrm{B}$ are…

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