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If n(A) = 12, n(b) = 9 and n(AuB) = 16 then find the value of n (A-B)​

User Acoelhosantos
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1 Answer

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Question has a slight error .we should find n(A
\capB)

  • n(A)=12
  • n(B)=9.
  • $n(A\cup B)=16$


\boxed{\sf n(A\cup B)=n(A)+n(B)-n(A\cap B)}


\\ \rm\longmapsto n(A\cap B)=n(A)+n(B)-n(A\cup B)


\\ \rm\longmapsto n(A\cap B)=12+9-16


\\ \rm\longmapsto n(A\cap B)=5

User Jmbeck
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